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Chemical Structure| 50-81-7
Chemical Structure| 50-81-7
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Product Details of [ 50-81-7 ]

CAS No. :50-81-7 MDL No. :MFCD00064328
Formula : C6H8O6 Boiling Point : -
Linear Structure Formula :- InChI Key :CIWBSHSKHKDKBQ-JLAZNSOCSA-N
M.W : 176.12 Pubchem ID :54670067
Synonyms :
L-Ascorbate;Vitamin C;Ascorbic acid, L-Ascorbic acid;NSC 218455;NSC 33832;Ascorbate

Calculated chemistry of [ 50-81-7 ]

Physicochemical Properties

Num. heavy atoms : 12
Num. arom. heavy atoms : 0
Fraction Csp3 : 0.5
Num. rotatable bonds : 2
Num. H-bond acceptors : 6.0
Num. H-bond donors : 4.0
Molar Refractivity : 35.12
TPSA : 107.22 Ų

Pharmacokinetics

GI absorption : High
BBB permeant : No
P-gp substrate : No
CYP1A2 inhibitor : No
CYP2C19 inhibitor : No
CYP2C9 inhibitor : No
CYP2D6 inhibitor : No
CYP3A4 inhibitor : No
Log Kp (skin permeation) : -8.54 cm/s

Lipophilicity

Log Po/w (iLOGP) : -0.31
Log Po/w (XLOGP3) : -1.64
Log Po/w (WLOGP) : -1.41
Log Po/w (MLOGP) : -2.6
Log Po/w (SILICOS-IT) : -1.15
Consensus Log Po/w : -1.42

Druglikeness

Lipinski : 0.0
Ghose : None
Veber : 0.0
Egan : 0.0
Muegge : 1.0
Bioavailability Score : 0.56

Water Solubility

Log S (ESOL) : 0.23
Solubility : 301.0 mg/ml ; 1.71 mol/l
Class : Highly soluble
Log S (Ali) : -0.1
Solubility : 140.0 mg/ml ; 0.793 mol/l
Class : Very soluble
Log S (SILICOS-IT) : 1.49
Solubility : 5460.0 mg/ml ; 31.0 mol/l
Class : Soluble

Medicinal Chemistry

PAINS : 0.0 alert
Brenk : 0.0 alert
Leadlikeness : 1.0
Synthetic accessibility : 3.47

Safety of [ 50-81-7 ]

Signal Word:Warning Class:N/A
Precautionary Statements:P261-P264-P270-P271-P280-P301+P312+P330-P302+P352-P304+P340+P312-P305+P351+P338-P332+P313-P337+P313-P362-P403+P233-P405-P501 UN#:N/A
Hazard Statements:H302-H315-H319-H335 Packing Group:N/A
GHS Pictogram:

Application In Synthesis of [ 50-81-7 ]

* All experimental methods are cited from the reference, please refer to the original source for details. We do not guarantee the accuracy of the content in the reference.

  • Upstream synthesis route of [ 50-81-7 ]
  • Downstream synthetic route of [ 50-81-7 ]

[ 50-81-7 ] Synthesis Path-Upstream   1~54

  • 1
  • [ 50-81-7 ]
  • [ 15667-21-7 ]
YieldReaction ConditionsOperation in experiment
70% With dihydrogen peroxide; sodium carbonate In water at 0 - 42℃; for 0.583333 h; Iso-ascorbic acid (17.6g, 0.1mol) was dissolved in 250ml of water and cooling to 0 ~ 6°C . Anhydrous sodium carbonate powder (21.2g, 0.2mol) was added portionwise reaction flask. After completion of the addition, stirring was continued while adding 30percent hydrogen peroxide (22mL), the internal temperature was increased from 6 to 19°C , stirring was continued in an ice bath for 5 minutes, the internal temperature rose to 27°C . The reaction solution was heated with stirring to 42°C 30 minutes. Zinc powder (1.0g, 0.015mol) was added to the reaction mixture was quenched with an excess of hydrogen peroxide, potassium iodide starch test paper showed negative. The reaction solution was adjusted with 6N hydrochloric acid to pH 1.0. Concentrated under reduced pressure at 50°C to a small volume to precipitate a white solid. With ethyl acetate (150mlx3) extraction. The organic phase was concentrated to 200ml (10 ~ 15vol); cooling to 15 ~ 25°C , stirring for 5 to 8 hours; (a lot of white solid precipitated) was filtered, dried to give 8.26g (3R, 4R) -3,4- two hydroxy-dihydro-furan -2 (3H) - one, a yield of 70percent
Reference: [1] Journal of the Chemical Society - Perkin Transactions 1, 1997, # 7, p. 1013 - 1016
[2] Patent: CN105503903, 2016, A, . Location in patent: Paragraph 0270; 0271; 0272; 0273
  • 2
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  • [ 1128-23-0 ]
YieldReaction ConditionsOperation in experiment
96% With hydrogen In water at 18℃; for 62 h; [0163] To a solution of L-ascorbic acid (83.9 g, 0.477 mol) in water (600 mL) was added Pd/C (10percent, 8.3 g). The mixture was subjected to hydrogenation in a Parr hydrogenator at 48 psi, 18° C. for 62 hours. The reaction mixture was filtered and the filtrate was concentrated in vacuo to afford L-gulonic y-lactone (81.0 g, 96percent) as an off-white solid, after drying at 50° C. in a vacuum oven for 18 hours: mp 182-184° C.
95% With 5% rhodium on activated aluminium oxide; hydrogen In water at 20℃; for 1.5 h; L-Ascorbic acid 4 (6.00 g, 34.10 mmol) was reduced by using 5 percent Rhon alumina (600 mg) in 50 mL of distilled water under 50 psi hydrogenpressure for 90 min in Parr hydrogenator at room temperature. Aftercompletion of reaction, (TLC check) reaction mixture was filtered through celite bed and washed with distilled water; the filtrate was concentrated under vacuo.Crude product was recrystallized from water to give pure 5 (5.80 g, 32.6 mmol, 95 percent) as a whitesolid. M.p. 185 °C. [α]D25 +22.5 (c 0.66, MeOH). IR (neat) νmax = 3443, 2925, 1790, 1215, 758,670 cm-1.1H NMR (400 MHz, D2O) δ = 4.67 (d, J = 4.6 Hz, 1H), 4.48 (dd, J = 4.6, 2.9 Hz, 1H),4.44 (dd, J = 8.3, 2.9 Hz, 1H), 4.03-3.96 (m, 1H), 3.73 (dd, J = 12.1, 3.4 Hz, 1H), 3.62 (dd, J =12.1, 5.6 Hz, 1H) ppm. 13C NMR (100 MHz, D2O) δ = 177.92, 81.31, 70.78, 70.05, 69.54, 61.46ppm. HRMS (ESI) m/z calcd for C6H10NaO6 [M+Na]+ 201.0370; found: 201.0372.
Reference: [1] Journal of Organic Chemistry, 1981, vol. 46, # 14, p. 2976 - 2977
[2] Patent: US2004/54172, 2004, A1,
[3] Patent: US2003/232889, 2003, A1, . Location in patent: Page/Page column 12
[4] Synlett, 2017, vol. 28, # 8, p. 970 - 972
[5] Tetrahedron Asymmetry, 1996, vol. 7, # 9, p. 2711 - 2720
[6] Chemistry - A European Journal, 2013, vol. 19, # 8, p. 2895 - 2902
[7] Journal of Organic Chemistry, 2005, vol. 70, # 24, p. 9892 - 9904
[8] Canadian Journal of Chemistry, 2006, vol. 84, # 10, p. 1351 - 1362
[9] Recueil des Travaux Chimiques des Pays-Bas, 1985, vol. 104, # 10, p. 266 - 272
[10] Organic Letters, 2010, vol. 12, # 22, p. 5226 - 5229
[11] Journal of the Chemical Society, Chemical Communications, 1988, # 18, p. 1221
[12] Synthetic Communications, 1995, vol. 25, # 20, p. 3263 - 3265
[13] Chemistry - A European Journal, 2012, vol. 18, # 31, p. 9651 - 9668
  • 3
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  • [ 1128-23-0 ]
Reference: [1] Patent: US2004/6245, 2004, A1, . Location in patent: Page 42
  • 4
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  • [ 15042-01-0 ]
YieldReaction ConditionsOperation in experiment
89% With trichlorophosphate In acetone at 20℃; for 4 h; To a magnetically stirred solution of AA (1.76 g, 10 mmol) in acetone (9 mL), phosphorus oxychloride (0.5 mL) was added and the reaction mixture was stirredfor 4 h at RT. Then it was filtered, washed with cold acetone–water and dried invacuo, leading to 5,6-O-isopropylidene-L-ascorbic acid 19 being obtained as colorless granules (1.92 g, 89percent). IR (KBr, cm-1): νmax 3242.6, 2993.3, 2907.6, 2741.6, 1755.5, 1665.4. 1H NMR (600 MHz, CD3COCD3): δ 4.71–4.73 (m, 1H, C4-H), 4.37–4.39 (m, 1H, C5-H), 4.16–4.21 (m, 1H, C6-H), 3.99–4.03 (m, 1H, C6-H), 1.29 (s, 6H, Me).
Reference: [1] Research on Chemical Intermediates, 2017, vol. 43, # 10, p. 5901 - 5916
[2] Chemische Berichte, 1936, vol. 69, p. 879
[3] Nature (London, United Kingdom), 1932, vol. 130, p. 847
[4] Justus Liebigs Annalen der Chemie, 1947, vol. 558, p. 177,181
[5] Patent: US2002/156051, 2002, A1,
[6] Patent: US4999437, 1991, A,
[7] Patent: US4552888, 1985, A,
[8] Patent: EP411183, 1991, A1,
[9] Patent: EP411184, 1991, A1,
  • 5
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YieldReaction ConditionsOperation in experiment
91% at 20 - 30℃; for 2 h; Inert atmosphere; Industry scale i)
5,6-O-Isopropylidene-L-Ascorbic Acid
To a mixture of L-ascorbic acid (65 kg, 369 mol), acetone (283 kg) and 2,2-dimethoxypropane (46 kg, 443 mol) was charged p-toluenesulfonic acid (1.1 kg, 5.5 mol).
Temperature was adjusted to 25±5° C.
The slurry was stirred for 2 hours, during which time nitrogen was frequently flushed through the bottom valve to prevent material from settling at the bottom of the reactor. NMR analysis (solvent: D2O) then showed 98.5percent conversion.
Heptanes (222 kg) were charged and the temperature adjusted to 5±5° C.
The reaction mixture was stirred for at least 30 minutes before filtering.
Remains of the acetonide product in the reactor were rinsed onto the filter cake using the mother liquors.
The filter cake was washed with heptanes (111 kg) and dried at 50° C. to give 5,6-O-isopropylidene-L-ascorbic acid (73 kg, 336 mol) as an almost white powder. Yield: 91percent.
1H NMR (400 MHz, d6-DMSO, with maleic acid and TFA) δ4.71 (d, J=3.0 Hz, 1H), 4.28 (m, 1H), 4.11 (dd, J=7.0, 8.4 Hz, 1H), 3.90 (dd, J=6.3, 8.4 Hz, 1H), 1.27 (s, 6H).
91% With toluene-4-sulfonic acid In acetone at 25℃; for 2 h; Inert atmosphere; Large scale To a mixture of L-ascorbic acid (65 kg, 369 mol), acetone (283 kg) and 2,2- dimethoxypropane (46 kg, 443 mol) was charged /?-toluenesulfonic acid (1.1 kg, 5.5 mol). Temperature was adjusted to 25±5°C. The slurry was stirred for 2 hours, during which time nitrogen was frequently flushed through the bottom valve to prevent material from settling at the bottom of the reactor. NMR analysis (solvent: D20) then showed 98.5 percent conversion. Heptanes (222 kg) were charged and the temperature adjusted to 5±5°C. The reaction mixture was stirred for at least 30 minutes before filtering. Remains of the acetonide product in the reactor were rinsed onto the filter cake using the mother liquors. The filter cake was washed with heptanes (111 kg) and dried at 50°C to give 5,6-O-isopropylidene-L-ascorbic acid (73 kg, 336 mol) as an almost white powder. Yield: 91percent. 1H NMR (400 MHz, d6-DMSO, with maleic acid and TFA) δ 4.71 (d, J= 3.0 Hz, 1H), 4.28 (m, 1H), 4.11 (dd, J= 7.0, 8.4 Hz, 1H), 3.90 (dd, J= 6.3, 8.4 Hz, 1H), 1.27 (s, 6H).
91% With toluene-4-sulfonic acid In acetone at 20 - 30℃; for 2 h; Inert atmosphere; Industrial scale To a mixture of L-ascorbic acid (65 kg, 369 mol), acetone (283 kg) and 2,2-dimethoxypropane (46 kg, 443 mol) was charged /p-toluenesulfonic acid (1.1 kg, 5.5 mol). Temperature was adjusted to 25±5°C. The slurry was stirred for 2 hours, during which time nitrogen was frequently flushed through the bottom valve to prevent material from settling at the bottom of the reactor. NMR analysis (solvent: D20) then showed 98.5 percent conversion. Heptanes (222 kg) were charged and the temperature adjusted to 5±5°C. The reaction mixture was stirred for at least 30 minutes before filtering. Remains of the acetonide product in the reactor were rinsed onto the filter cake using the mother liquors. The filter cake was washed with heptanes (111 kg) and dried at 50°C to give 5,6-O-isopropylidene-L-ascorbic acid (73 kg, 336 mol) as an almost white powder. Yield: 91percent. 1H NMR (400 MHz, d6-DMSO, with maleic acid and TFA) δ 4.71 (d, J= 3.0 Hz, 1H), 4.28 (m, 1H), 4.11 (dd, J= 7.0, 8.4 Hz, 1H), 3.90 (dd, J= 6.3, 8.4 Hz, 1H), 1.27 (s, 6H).
86% With camphor-10-sulfonic acid In acetone at 20℃; This material was prepared according to literature precedence (Bioorg. Med. Chem. 2003, vol. 11, 827). To a suspension of L-ascorbic acid (20.0 g, 114 mmol) in acetone (200 mL) was added 2,2-dimethoxypropane (20.4 g, 196 mmol) and 10- camphorsulfonic acid (1.32 g, 5.68 mmol). The resultant mixture was allowed to stir overnight at room temperature. To the resultant slurry was added approximately 0.6 g tri ethyl amine. A portion of hexane was added to the mixture, and the white precipitate was collected via vacuum filtration, washing with additional hexane. The material was dried under vacuum to afford the desired product (21.0 g, 86percent yield). NMR was consistent with the desired product.
82% With tin(ll) chloride In acetone for 6 h; Reflux A mixture of l-Ascorbic acid compound 1 g (2 mmol) and acetone(15 mL) was stirred for 15 min. 2,2-Dimethoxy propane(1.25 mL) and catalytic amount of tin chloride was added to thereaction mixture and it was refluxed for 6 h. Cooled the reactionmixture to 5-10 °C and stirred for 45 min at room temperature.The precipitated was filtered, washed with acetone and dried toget the compound 2A. Yield: 82percent; M.P: 206 C. TLC: 100 DCM: 20EA: 10 ethanol: 1 Acetic acid.
79% With hydrogenchloride In methanol at 20 - 25℃; for 4 h; To the solution of L-Ascorbic acid (100 g, 568 mmol) in 200 mL acetone was treated with 2,2-dimethoxypropane (118 g, 1.13 mmol), and Hydrochloric acid (4 M in methanol, 60 mL). The reaction mixture was stirred at room temperature for 4 h. the mixture was filtered and the filter cake was washed with 10 mL acetone and dried in vacuum to afford 37 (90 g, 79percent) as a white solid.
50 mg With hydrogenchloride In acetone at 25 - 30℃; for 4 h; A mixture of L-Ascorbic acid compound of formula-3 (50 gm) and acetone (250 ml) was stirred for 15 minutes. 2,2-Dimethoxy propane (62.5 ml) was added to the reaction mixture. Acidified the reaction mixture by using HCl gas and stirred for 4 hrs at 25-30°C. Cooled the reaction mixture to 5-10°C and stirred for 45 minutes at the same temperature. The precipitated solid was filtered, washed with acetone and dried to get the title compound. Yield: 50 gm; M.R: 205-210°C.

Reference: [1] Tetrahedron Asymmetry, 1997, vol. 8, # 14, p. 2299 - 2302
[2] Tetrahedron Letters, 2002, vol. 43, # 2, p. 213 - 216
[3] Journal of Organic Chemistry, 1985, vol. 50, # 19, p. 3462 - 3467
[4] Tetrahedron: Asymmetry, 1991, vol. 2, # 5, p. 359 - 362
[5] Patent: US2012/15927, 2012, A1, . Location in patent: Page/Page column 8
[6] Patent: WO2013/8002, 2013, A1, . Location in patent: Page/Page column 39
[7] Patent: EP2740458, 2016, B1, . Location in patent: Paragraph 0045
[8] Tetrahedron, 2013, vol. 69, # 9, p. 2157 - 2166
[9] Patent: WO2017/95704, 2017, A1, . Location in patent: Page/Page column 53
[10] Bioorganic Chemistry, 2019, vol. 82, p. 178 - 191
[11] European Journal of Medicinal Chemistry, 2018, vol. 151, p. 98 - 109
[12] Tetrahedron Letters, 2004, vol. 45, # 28, p. 5395 - 5398
[13] Tetrahedron Letters, 1990, vol. 31, # 7, p. 1002 - 1006
[14] Synthesis, 1995, # 6, p. 687 - 692
[15] Patent: US4567282, 1986, A,
[16] Patent: US4502994, 1985, A,
[17] Carbohydrate Research, 2009, vol. 344, # 15, p. 2100 - 2104
[18] Bulletin of the Korean Chemical Society, 2012, vol. 33, # 7, p. 2213 - 2218
[19] Patent: WO2016/207907, 2016, A1, . Location in patent: Page/Page column 18
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  • [ 15042-01-0 ]
YieldReaction ConditionsOperation in experiment
91% at 5 - 20℃; for 22.5 h; Inert atmosphere To a solution of L-ascorbic acid 5 (20.01 g, 113.6 mmol, 1.0 eq) in acetone (80 mL) was added acetyl chloride (2.1 mL, 29.9 mmol, 0.26 eq) at room temperature. After stirring for 3.5 h at room temperature, the reaction mixture was stored in the refrigerator (5 °C) for 19 h. The solid was then filtered off and washed with a small amount of cold acetone to afford 6 as a colorless solid (22.36 g, 103.4 mmol, 91percent)
Reference: [1] Tetrahedron Letters, 2016, vol. 57, # 52, p. 5899 - 5901
[2] Patent: US6602906, 2003, B1,
[3] Patent: US5552520, 1996, A,
[4] Patent: US5607968, 1997, A,
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YieldReaction ConditionsOperation in experiment
95% With toluene-4-sulfonic acid In dimethyl sulfoxide; acetone at 50℃; for 5 h; Example 1
Synthesis of 5,6-O-isopropylidene Ascorbic Acid
To the mixed solvent composed of 100 mL of dimethylsulfoxide and 40 ml of acetone were added 17.6 g of L-ascorbic acid, 15.6 g of 1,2-dimethoxypropane and 1.2 g of p-tolusulfonic acid, followed by stirring for 5 hours at 50° C.
The produced reaction mixture was vacuum-distillated at 20° C. to eliminate the remaining acetone and non-reacted 1,2-dimethoxypropane to give 20.5 g of the target compound (yield: 95percent).
Reference: [1] Patent: US2010/48919, 2010, A1, . Location in patent: Page/Page column 2-3
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YieldReaction ConditionsOperation in experiment
95% With 1,2-dimethoxypropane; toluene-4-sulfonic acid In dimethyl sulfoxide at 50℃; for 5 h; To the mixed solvent composed of 100 mL of dimethylsulfoxide and 40 ml of acetone were added 17.6 g of L- ascorbic acid, 15.6 g of 1, 2-dimethoxypropane and 1.2 g of p- tolusulfonic acid, followed by stirring for 5 hours at 50 °C The produced reaction mixture was vacuum-distillated at 20 °C to eliminate the remaining acetone and non-reacted 1,2- dimethoxypropane to give 20.5 g of the target compound (yield: 95percent) .
94.4% for 4 h; Cooling with ice To a 100 mL single flask was added 3.52 g of vitamin C, 2.76 g of p-toluenesulfonic acid, 15 mL of acetone, ice bath condition 4h, The filter cake was washed with ethyl acetate and dried in vacuo to give 4.08 g of 5,6-O-isopropylidene-L-ascorbic acid as a white solid in a yield of 94.4percent.
86% at 20℃; for 3 h; Preparation Example 1 : Preparation of ---5,6-O-isopropylidin-ascorbic acid; L-5,6-O-isopropylidin-ascorbic acid was prepared according to a method disclosed in Journal of the American Chemical Society, Vol. 102, No. 20, pp 6304,1980. That is, 100 g of ascorbic acid was added to 50 ml of acetone. While the reaction mixture was stirred at room temperature, 10 ml of acetyl chloride was <n="16"/>added to the mixture, which was then stirred for 3 hours. The mixture was cooled in ice bath and filtered to isolate a precipitate. The precipitate was washed with 500 ml of cold acetone and dried under reduced pressure to obtain 105 g of L-δ.e-O-isopropylidin-ascorbic acid (yield: 86percent, mp: 206-208 °C). 1H NMR (400MHz, CDCL3), Chemical shift; 5.50 (1 H, d), 5.18 (1 H1 m),4.20(2H, t), 2.52(2H, m), 2.51 (4H, t), 2.25-1.55 (12H, m)
85% at 0℃; for 24 h; FORMATION of one of the cholesterol absorption inhibitors described herein: Disodium ASCORBYL PHOSPHATE E RRE To a dry round bottom flask, acetone (150 ML) and L-ascorbic acid (50 g) were added at 0 °C. Acetyl chloride (7.5 ML was added dropwise through an addition funnel in 10 minutes. The reaction mixture was stirred at 0 °C for 24 hours. The precipitate was filtered off and washed with acetone (3X20 ML). The white product, 5, 6-ISOPROPYLIDINE ascorbic acid, was dried under vacuum for 1.5 hours to give a dry powder (52 g), yield 85percent. A dry three neck round bottom flask was fitted with a stirring bar, argon inlet and an addition funnel. A solution of dehydroisoandrosterone (1.73 g, 6 MMOL) in anhydrous THF (15 ml) and pyridine (2.4 ml) was added dropwise to the mixture of anhydrous THF (12 ml) and POCI3 (0.7 ML, 7.5 MMOL) at 0 °C over a period of 10 minutes. A white precipitate formed immediately. The suspension was stirred at 0 °C for 40 minutes, and at room temperature for 1 hour and 40 minutes. To the above suspension, a solution of 5, 6-ISOPROPYLIDINE ascorbic acid (3.6 g, 16.67 MMOL) in anhydrous pyridine (3 ml) and THF (30 ml) was added dropwise at 0 °C over a period of 20 minutes. The suspension was stirred at 0 °C for 30 minutes, and at room temperature for 1.5 hours. The formed pyridinium chloride was filtered out and washed with THF twice. The solvents were evaporated under reduced pressure at 40 °C to afford a residue. The residue was dissolved in THF (40 ML), and 2N HCI (30 ml) was added in one portion. The mixture was stirred at room temperature for 8 hours. THF was evaporated under a reduced pressure. The water layer was extracted with ethyl acetate (4X50 ML). The combined ethyl acetate solution was washed with brine (100 ML), and dried over NA2SO4. The solvent was evaporated to give a residue. The residue was dissolved in CHCI3, and then hexanes was added to precipitate the product. The precipitated solid was filtered out, washed with hexanes and dried under vacuum (2.43 g, crude product, yield : 77percent). The purification of phosphate ester was done by reverse phase C-18 chromatography (Waters, water/methanol = 90/10 to 60/40). Pure compound 4 (Figure 1,39 mg) was isolated from 50 mg of the crude product. The overall yield (base on dehydroisoandrosterone) was 60 percent. ASCORBYL phosphate ester of dehydroisoandrosterone (0.5 g, 0.95 MMOL) was dissolved in methanol (3 ml) at room temperature, and then sodium methoxide in methanol (1ML, 20percent) was added. The suspension was stirred at room temperature for 30 minutes. The precipitated solid was filtered out, washed with methanol, acetone and hexanes. The mother liquor was concentrated to 2 mi, acetone was added to precipitate the product. An additional white solid was obtained. The combined solid was dried under vacuum at room temperature. Disodium ascorbyl phosphate ester of dehydroisoandrosterone (0.49 G, yield 91 percent) was obtained.
85% at 0℃; for 24 h; To a dry round bottom flask, acetone (150 ml) and L-ascorbic acid (50 g) were added at 0 C. Acetyl chloride (7.5 ml) was added dropwise through an addition funnel in 10 minutes. The reaction mixture was stirred at 0 C. for 24 hours. The precipitate was filtered off and washed with acetone (3x20 ml). The white product, 5,6-isopropylidine ascorbic acid, was dried under vacuum for 1.5 hours to give a dry powder (52 g), yield 85percent.
80.6% at 25℃; 250 ?l of acetyl chloride are added to a suspension of vitamin C, or ascorbic acid (3 g, 17 mmol) in 30 ml of acetone. The solution becomes clear and a white precipitate then forms. After reaction overnight, the precipitate is filtered off and then rinsed with ice-cold ethyl acetate. The powder obtained is then dried to give 2.96 g (13.7 mmol) of protected vitamin C (CV-100), i.e. an 80.6percent yield.
80% at 25 - 30℃; for 5 h; Methanesulfonic acid (13 mL, 0.200 mol) was dropwised to slurry of L-ascorbic acid (10 g, 0.568 mol) in acetone (400 mL). The mixture was stirred at 25-30° C. After 5 hours, the crystalline product separated. The crystals were collected by filtration, washed with cool acetone and dried in vacuum desiccators at 40° C. Gave 100 g of Formula I (0.463 mol; yield 80percent).
80.2% at -5 - 20℃; To a dried 1 L three-necked flask, 91.0 g of ascorbic acid and 450 mL of acetone were added. The temperature was cooled to -5° C. in an ice-salt bath; 200.0 g of concentrated sulfuric acid was dropped slowly for approximately 2.5 hours and the internal temperature of the solution was controlled to 0-5° C., stirred for 5.0 min, then the ice-salt bath was moved away; the temperature was increased naturally to room temperature, and the reaction was continued for 45 minutes; the reacting solution changed from colorless to pale yellow; then the reacting solution was subjected to vacuum filtration under reduced pressure and the filter cake was washed for several times with a small amount of acetone until the pH value was neutral; the filter cake was dried at 50° C. in a vacuum for 1-2 hours and 89.5 g of white solid powder was obtained the melting point of which is 215-217° C. The yield was 80.2percent.
74% at 20℃; 5,6-Isopropylidene-L-ascorbic acid
followed the procedure reported by Jung and Shaw (J. Am. Chem. Soc, 102 [1980] 6304). L-Ascorbic acid (10.01 g, 0.0568 mol) was added to a 125 mL Erlenmeyer flask with approximately 50 mL of acetone (0.681 mol). The slurry was stirred as 1 mL of acetyl chloride (0.0140 mol) was added. The mixture was corked, sealed with Parafilm and left to stir at room temperature for 2-3 hours. The flask was then stored in a refrigerator (7 °C) for 20-24 hours. The solid from this mixture was isolated by vacuum filtration, and was rinsed with cold acetone. After drying at room temperature, the solid weighed 9.09 g, (74percent). The identity of the solid as 5,6-isopropylidene-L-ascorbic acid was confirmed by NMR and a melting point of 202-205 °C (crude literature [J. Am. Chem. Soc, 102 (1980) 6304]: 195-200 °C); recrystallization from acetone/hexane did not improve the melting point (recrystallized literature [Can. J. Chem., 47 (1969) 2498]: 217-222 °C). 1H NMR (Me2SO-d6) δ 1.255 (6H, s), 3.882 (1H, dd, J= 8.0, 6.8 Hz), 4.098 (1H, dd, J= 7.8, 8.0 Hz), 4.2615 (1H, td, J- 2.8, 6.6 Hz), 4.7095 (1H, d, 2.8 Hz), 8.482 (1H, s), 1 1.293 (1H, s).
67.2% at 20℃; for 2 h; Ascorbic acid (4g, 22.7mmol) was suspended in 2.5ml of anhydrous acetone. A catalytic amount of acetyl chloride (1.76ml, 24.7mmol) was then added and the reaction mixture was stirred for 2 hours at room temperature using a calcium chloride drying tube. The slurry was cooled to O0C, filtered, washed with cold acetone and dried under vacuum to yield 5,6-O-isopropylidene-ascorbic acid (3.57g, yield: 67.2percent) as a white solid. <n="17"/>1H NMR (d6-DMSO) δ 1.23 (6 H, s, 2 CHJ), 3.86 - 3.88 (1 η, dd, -0-CHH-CH(O)-), 4.05 -4.09 (1 H, dd, -0-CHZZ-CH(O)-), 4.24 - 4.25 (1 H, td, -O-CH2 -CH(O)-CH-), 4.71 (1 H, d,CH2-CH(O)-CZZ(O)-), 8.43 (1 H, broad s, OH), 1 1.27 (1 η, broad s, OH).13C NMR (d6-DMS0) 6 25.53, 25.92, 64.97, 73.54, 74.36, 109.13, 1 18.28, 152.51 , 170.37MS-ESI mlz 234.09 [M + Nη4]+CHN: Found (C=49.36percent, 5.65percent), Theoretical (C=50.00percent, 5.59percent)
11.3 g at 0 - 20℃; for 3 h; To 10.1 g of ascorbic acid was added 50 ml of acetone, and the mixture was stirred. 0.85 g (0.011 mol) of acetyl chloride was added slowly at 0 °C, and the mixture was stirred at room temperature for 3 hours. The reaction solvent was removed and the residue was subjected to silica gel column chromatography with ethyl acetate and n-hexane (1: 3) to obtain 8.66 g of white solid title compound.
9.55 g at 20℃; for 3 h; As vitamin C, L-ascorbic acid (10 g, 55 mmol) manufactured by Wako Pure Chemical Industries, Ltd. was dissolved in acetone, acetyl chloride (1 ml, 15 mmol) was added, and the mixture was stirred at room temperature for 3 hours. The solid was separated by filtration, and the obtained solid was washed with acetone and then dried to obtain 5,6-isopropylidene vitamin C (aka: 5,6-isopropylidene ascorbic acid) of the chemical formula 18 (9.55 g, 44.2 mmol) was obtained as a white solid.
19.6 g With toluene-4-sulfonic acid In dimethyl sulfoxide at 25℃; for 5 h; 20.6 g of L-ascorbic acid and 1.7 g of p-toluenesulfonic acid were added to a mixed solution of 100 ml of dimethyl sulfoxide and 40 ml of acetone to prepare an ascorbic acid solution.And the mixture was stirred at 25 DEG C for 5 hours to synthesize 3-O-isopropylidene ascorbic acid in the solution. At this time, the termination time of the reaction is determined by thin layer chromatography (TLC)After the reaction was completed, the solution was dried to obtain 19.6 g of 3-O-isopropylidene ascorbic acid.

Reference: [1] Acta Chemica Scandinavica, 1995, vol. 49, # 4, p. 297 - 300
[2] Tetrahedron Letters, 2010, vol. 51, # 32, p. 4199 - 4201
[3] Tetrahedron, 2005, vol. 61, # 18, p. 4341 - 4346
[4] Patent: WO2008/44809, 2008, A1, . Location in patent: Page/Page column 9
[5] Patent: CN104370977, 2017, B, . Location in patent: Paragraph 0018
[6] European Journal of Medicinal Chemistry, 2016, vol. 110, p. 376 - 388
[7] Patent: WO2009/14343, 2009, A2, . Location in patent: Page/Page column 14-15
[8] Patent: WO2005/30225, 2005, A2, . Location in patent: Page/Page column 41
[9] Patent: US2005/234025, 2005, A1, . Location in patent: Page/Page column 15; sheet 1
[10] Journal of Medicinal Chemistry, 1988, vol. 31, # 4, p. 793 - 798
[11] Journal of the American Chemical Society, 1980, vol. 102, # 20, p. 6304 - 6311
[12] Organic Letters, 2018, vol. 20, # 18, p. 5849 - 5852
[13] Tetrahedron Letters, 1989, vol. 30, # 19, p. 2505 - 2508
[14] Patent: US2004/236098, 2004, A1, . Location in patent: Page 6
[15] Patent: US2010/56809, 2010, A1, . Location in patent: Page/Page column 3
[16] Patent: US2010/204464, 2010, A1, . Location in patent: Page/Page column 5-6
[17] Chemistry - A European Journal, 2005, vol. 11, # 8, p. 2525 - 2536
[18] Bulletin of the Chemical Society of Japan, 1996, vol. 69, # 3, p. 725 - 734
[19] Carbohydrate Research, 1996, vol. 286, p. 123 - 138
[20] Molecules, 2007, vol. 12, # 11, p. 2533 - 2545
[21] Patent: WO2015/48121, 2015, A1, . Location in patent: Paragraph 000230
[22] Medicinal Chemistry Research, 2008, vol. 17, # 2-7, p. 53 - 61
[23] Synthesis, 2011, # 4, p. 555 - 562
[24] Chinese Chemical Letters, 2013, vol. 24, # 2, p. 117 - 119
[25] Patent: WO2008/110813, 2008, A2, . Location in patent: Page/Page column 15-16
[26] Tetrahedron: Asymmetry, 1995, vol. 6, # 5, p. 1181 - 1190
[27] Organic and Biomolecular Chemistry, 2005, vol. 3, # 13, p. 2450 - 2457
[28] Synthetic Communications, 1989, vol. 19, # 20, p. 3529 - 3534
[29] Journal of Molecular Structure, 2004, vol. 687, # 1-3, p. 101 - 106
[30] Tetrahedron Asymmetry, 1998, vol. 9, # 8, p. 1359 - 1367
[31] Bioorganic and Medicinal Chemistry Letters, 1998, vol. 8, # 13, p. 1703 - 1706
[32] Australian Journal of Chemistry, 1999, vol. 52, # 2, p. 137 - 142
[33] Bioorganic and Medicinal Chemistry Letters, 2006, vol. 16, # 20, p. 5313 - 5316
[34] Patent: WO2005/30225, 2005, A2, . Location in patent: Page/Page column 40
[35] Patent: US2005/234025, 2005, A1, . Location in patent: Page/Page column 18; sheet 7; 8
[36] Patent: WO2009/51460, 2009, A2, . Location in patent: Page/Page column title page; 16-17
[37] Chemistry - A European Journal, 2010, vol. 16, # 43, p. 12935 - 12940
[38] Patent: US2013/102649, 2013, A1, . Location in patent: Paragraph 0251; 0252
[39] European Journal of Medicinal Chemistry, 2014, vol. 82, p. 314 - 323
[40] Patent: KR101491728, 2015, B1, . Location in patent: Paragraph 0090-0092
[41] Patent: JP2016/44171, 2016, A, . Location in patent: Paragraph 0075; 0076
[42] RSC Advances, 2017, vol. 7, # 2, p. 791 - 800
[43] Patent: KR2017/11019, 2017, A, . Location in patent: Paragraph 0116; 0123-0125
[44] European Journal of Medicinal Chemistry, 2017, vol. 135, p. 110 - 116
[45] Patent: KR2016/143901, 2016, A, . Location in patent: Paragraph 0025; 0026; 0027; 0028; 0029
[46] Archiv der Pharmazie, 2018, vol. 351, # 5,
  • 9
  • [ 50-81-7 ]
  • [ 15042-01-0 ]
Reference: [1] Patent: EP411182, 1991, A1,
  • 10
  • [ 75-36-5 ]
  • [ 50-81-7 ]
  • [ 15042-01-0 ]
Reference: [1] Patent: US5536500, 1996, A,
  • 11
  • [ 814-68-6 ]
  • [ 50-81-7 ]
  • [ 15042-01-0 ]
Reference: [1] Doklady Chemistry, 1993, vol. 333, # 1-6, p. 290 - 292[2] Dokl. Akad. Nauk SSSR Ser. Khim., 1993, vol. 333, # 5, p. 730 - 731
  • 12
  • [ 623-65-4 ]
  • [ 57-10-3 ]
  • [ 50-81-7 ]
  • [ 137-66-6 ]
YieldReaction ConditionsOperation in experiment
91.3%
Stage #1: at 18℃; for 15 h;
Stage #2: at 28℃; for 20 h;
(1)500g of concentrated sulfuric acid was added to the three-necked flask, add 50g of palmitic acid, stirring to dissolve Solution in concentrated sulfuric acid was added 50gL- ascorbic acid, 18 ° C reaction 15h; (2)50g palmitic anhydride was added to the reaction mixture, the temperature was raised to 28 ° C, the reaction 20h, then After adding 10g of activated carbon and stirred for 15min; (3)The step (2) in the resulting mixture is added to 1250ml10 ° C cold water, filtered The filter cake is too crude, the crude product was rinsed with 100ml water, then washed with water after the crude product was dissolved in 750ml of butyl acetate, 50 ° C incubation decolorization 30min. Filtered and allowed to stand, stratification, the upper organic layer (Product containing layer) 50 ° C, washed twice with water, water per 500ml. After washing to the water layer, The organic layer was distilled off under reduced pressure to 400ml of butyl acetate, allowed to stand for cooling to 15 ° C, the solid was filtered off with 50ml The resulting solid was rinsed with ethyl acetate, drained, placed in a vacuum drying oven at 50 ° C. L-ascorbic acid-6-palmitate was obtained as a white flake with a purity of 98. 1percent and a yield of 91.3percent.
Reference: [1] Patent: CN105315244, 2016, A, . Location in patent: Paragraph 0047-0050
  • 13
  • [ 693-38-9 ]
  • [ 50-81-7 ]
  • [ 137-66-6 ]
Reference: [1] JAOCS, Journal of the American Oil Chemists' Society, 2011, vol. 88, # 1, p. 57 - 64
[2] Tetrahedron Letters, 1994, vol. 35, # 21, p. 3583 - 3584
  • 14
  • [ 57-10-3 ]
  • [ 50-81-7 ]
  • [ 137-66-6 ]
Reference: [1] JAOCS, Journal of the American Oil Chemists' Society, 2003, vol. 80, # 8, p. 795 - 799
[2] Journal of Molecular Catalysis B: Enzymatic, 2014, vol. 102, p. 127 - 131
[3] Ultrasonics Sonochemistry, 2011, vol. 18, # 5, p. 988 - 996
[4] JAOCS, Journal of the American Oil Chemists' Society, 2011, vol. 88, # 1, p. 57 - 64
[5] Oil and Soap (Alexandria, Egypt), 1943, vol. 20, p. 224
[6] Annales Pharmaceutiques Francaises, 1957, vol. 15, p. 691,693
[7] JAOCS, Journal of the American Oil Chemists' Society, 1999, vol. 76, # 11, p. 1291 - 1295
[8] Farmaco, 2003, vol. 58, # 12, p. 1271 - 1276
[9] Journal of Physical Chemistry B, 2014, vol. 118, # 11, p. 3053 - 3062
[10] Patent: CN103254160, 2016, B, . Location in patent: Paragraph 0017-0022
  • 15
  • [ 112-39-0 ]
  • [ 50-81-7 ]
  • [ 137-66-6 ]
Reference: [1] Synthetic Communications, 2009, vol. 39, # 7, p. 1143 - 1151
  • 16
  • [ 628-97-7 ]
  • [ 50-81-7 ]
  • [ 137-66-6 ]
Reference: [1] JAOCS, Journal of the American Oil Chemists' Society, 2011, vol. 88, # 1, p. 57 - 64
  • 17
  • [ 50-81-7 ]
  • [ 137-66-6 ]
Reference: [1] Bioorganic and Medicinal Chemistry Letters, 2006, vol. 16, # 20, p. 5313 - 5316
  • 18
  • [ 52-90-4 ]
  • [ 50-81-7 ]
  • [ 1708-32-3 ]
  • [ 188290-36-0 ]
  • [ 554-14-3 ]
  • [ 3581-91-7 ]
  • [ 74015-70-6 ]
  • [ 13623-11-5 ]
  • [ 88-15-3 ]
  • [ 24295-03-2 ]
  • [ 13679-72-6 ]
  • [ 867253-51-8 ]
Reference: [1] Food Chemistry, 2012, vol. 132, # 3, p. 1316 - 1323
  • 19
  • [ 52-90-4 ]
  • [ 50-81-7 ]
  • [ 1708-32-3 ]
  • [ 188290-36-0 ]
  • [ 554-14-3 ]
  • [ 3581-91-7 ]
  • [ 74015-70-6 ]
  • [ 13623-11-5 ]
  • [ 88-15-3 ]
  • [ 24295-03-2 ]
  • [ 13679-72-6 ]
  • [ 867253-51-8 ]
Reference: [1] Food Chemistry, 2012, vol. 132, # 3, p. 1316 - 1323
  • 20
  • [ 52-90-4 ]
  • [ 50-81-7 ]
  • [ 1940-01-8 ]
  • [ 1468-83-3 ]
  • [ 24295-03-2 ]
  • [ 251-41-2 ]
  • [ 23654-92-4 ]
  • [ 867253-51-8 ]
Reference: [1] Food Chemistry, 2010, vol. 121, # 4, p. 1060 - 1065
  • 21
  • [ 50-81-7 ]
  • [ 496-64-0 ]
Reference: [1] Agricultural and Biological Chemistry, 1983, vol. 47, # 2, p. 419 - 420
  • 22
  • [ 50-81-7 ]
  • [ 496-64-0 ]
  • [ 88-14-2 ]
Reference: [1] Journal of Agricultural and Food Chemistry, 2012, vol. 60, # 42, p. 10696 - 10701
  • 23
  • [ 56-45-1 ]
  • [ 50-81-7 ]
  • [ 109-08-0 ]
  • [ 123-32-0 ]
  • [ 271-89-6 ]
  • [ 13925-00-3 ]
  • [ 823-82-5 ]
  • [ 13360-65-1 ]
  • [ 1438-94-4 ]
  • [ 96-76-4 ]
  • [ 13360-64-0 ]
  • [ 21835-01-8 ]
Reference: [1] Food Chemistry, 2010, vol. 119, # 1, p. 214 - 219
  • 24
  • [ 56-45-1 ]
  • [ 50-81-7 ]
  • [ 109-08-0 ]
  • [ 123-32-0 ]
  • [ 13925-00-3 ]
  • [ 13238-84-1 ]
  • [ 13360-65-1 ]
  • [ 96-76-4 ]
  • [ 55138-63-1 ]
  • [ 13925-03-6 ]
  • [ 13360-64-0 ]
  • [ 15707-34-3 ]
Reference: [1] Food Chemistry, 2010, vol. 119, # 1, p. 214 - 219
  • 25
  • [ 56-45-1 ]
  • [ 50-81-7 ]
  • [ 109-08-0 ]
  • [ 123-32-0 ]
  • [ 13925-00-3 ]
  • [ 13238-84-1 ]
  • [ 13360-65-1 ]
  • [ 96-76-4 ]
  • [ 13925-03-6 ]
  • [ 18138-05-1 ]
  • [ 13360-64-0 ]
  • [ 21835-01-8 ]
Reference: [1] Food Chemistry, 2010, vol. 119, # 1, p. 214 - 219
  • 26
  • [ 56-45-1 ]
  • [ 50-81-7 ]
  • [ 109-08-0 ]
  • [ 123-32-0 ]
  • [ 13925-00-3 ]
  • [ 13238-84-1 ]
  • [ 13360-65-1 ]
  • [ 96-76-4 ]
  • [ 13925-03-6 ]
  • [ 13360-64-0 ]
  • [ 15707-34-3 ]
  • [ 21835-01-8 ]
Reference: [1] Food Chemistry, 2010, vol. 119, # 1, p. 214 - 219
  • 27
  • [ 72-19-5 ]
  • [ 50-81-7 ]
  • [ 123-32-0 ]
  • [ 13925-00-3 ]
  • [ 13238-84-1 ]
  • [ 13360-65-1 ]
  • [ 13925-03-6 ]
  • [ 18138-05-1 ]
  • [ 13360-64-0 ]
  • [ 15707-34-3 ]
  • [ 15707-23-0 ]
Reference: [1] Food Chemistry, 2010, vol. 119, # 1, p. 214 - 219
  • 28
  • [ 72-19-5 ]
  • [ 50-81-7 ]
  • [ 13925-00-3 ]
  • [ 13238-84-1 ]
  • [ 13360-65-1 ]
  • [ 1115-11-3 ]
  • [ 13925-03-6 ]
  • [ 18138-05-1 ]
  • [ 13360-64-0 ]
  • [ 15707-34-3 ]
  • [ 15707-23-0 ]
  • [ 18138-04-0 ]
Reference: [1] Food Chemistry, 2010, vol. 119, # 1, p. 214 - 219
  • 29
  • [ 52-90-4 ]
  • [ 50-81-7 ]
  • [ 1940-01-8 ]
  • [ 1468-83-3 ]
  • [ 24295-03-2 ]
  • [ 251-41-2 ]
  • [ 23654-92-4 ]
  • [ 867253-51-8 ]
Reference: [1] Food Chemistry, 2010, vol. 121, # 4, p. 1060 - 1065
  • 30
  • [ 52-90-4 ]
  • [ 50-81-7 ]
  • [ 1940-01-8 ]
  • [ 24295-03-2 ]
  • [ 251-41-2 ]
  • [ 13393-75-4 ]
  • [ 23654-92-4 ]
  • [ 867253-51-8 ]
Reference: [1] Food Chemistry, 2010, vol. 121, # 4, p. 1060 - 1065
  • 31
  • [ 52-90-4 ]
  • [ 50-81-7 ]
  • [ 1940-01-8 ]
  • [ 24295-03-2 ]
  • [ 251-41-2 ]
  • [ 13393-75-4 ]
Reference: [1] Food Chemistry, 2010, vol. 121, # 4, p. 1060 - 1065
  • 32
  • [ 52-90-4 ]
  • [ 50-81-7 ]
  • [ 1940-01-8 ]
  • [ 24295-03-2 ]
  • [ 251-41-2 ]
  • [ 13393-75-4 ]
  • [ 151602-63-0 ]
  • [ 867253-51-8 ]
Reference: [1] Food Chemistry, 2010, vol. 121, # 4, p. 1060 - 1065
  • 33
  • [ 52-90-4 ]
  • [ 50-81-7 ]
  • [ 1940-01-8 ]
  • [ 24295-03-2 ]
  • [ 251-41-2 ]
  • [ 867253-51-8 ]
Reference: [1] Food Chemistry, 2010, vol. 121, # 4, p. 1060 - 1065
  • 34
  • [ 52-90-4 ]
  • [ 50-81-7 ]
  • [ 1708-32-3 ]
  • [ 188290-36-0 ]
  • [ 554-14-3 ]
  • [ 3581-91-7 ]
  • [ 74015-70-6 ]
  • [ 13623-11-5 ]
  • [ 88-15-3 ]
  • [ 24295-03-2 ]
  • [ 13679-72-6 ]
  • [ 867253-51-8 ]
Reference: [1] Food Chemistry, 2012, vol. 132, # 3, p. 1316 - 1323
  • 35
  • [ 1452-15-9 ]
  • [ 95-54-5 ]
  • [ 50-81-7 ]
  • [ 71-36-3 ]
  • [ 148-79-8 ]
YieldReaction ConditionsOperation in experiment
87.1% With methanesulfonic acid In water EXAMPLE 18
Synthesis of thiabendazole using anhydrous methanesulfonic acid as the acid catalyst
To a 500 ml four-neck, round-bottom flask fitted with a mechanical stirrer, thermometer with N2 inlet and a condenser equipped with a water scrubber (200 ml of water) were charged 160 ml of 1-butanol and 0.1 g (5.7*10-4 mole) of ascorbic acid.
The entire assembly was flushed with N2 and a N2 sweep was maintained on the system for the duration of the reaction.
Following this, 54 g (0.5 mole) of o-phenylenediamine and 55 g (0.5 mole) of 4-cyanothiazole were charged to the reaction vessel.
Next, 26 ml (0.39 mole) of methanesulfonic acid were added dropwise to the reaction vessel and a 20° C. rise in the room temperature mixture was observed.
Subsequently, the mixture was heated to reflux, 127.5° C., and after 2 hours the reflux temperature decreased to 120° C.
After 6 hours at reflux, the reaction was determined to be complete via gas chromatography.
The same procedure as that described in Example 1 was used to transfer, isolate and dry thiabendazole.
The weight of dry thiabendazole crystals was 87.60 g, which corresponds to an 87.1percent yield.
The purity was determined to be 99.84percent (based on area percent) using HPLC analysis.
75.4% With acetic acid In water EXAMPLE 19
Synthesis of thiabendazole using anhydrous acetic acid as the acid catalyst
To a 500 ml four-neck, round-bottom flask fitted with a mechanical stirrer, thermometer with N2 inlet and a condenser equipped with a water scrubber (200 ml of water) were charged 75 ml of 1-butanol and 0.05 g (2.8*10-4 mole) of ascorbic acid.
The entire assembly was flushed with N2 and a N2 sweep was maintained on the system for the duration of the reaction.
Following this, 27 g (0.25 mole) of o-phenylenediamine, 27.5 g (0.25 mole) of 4-cyanothiazole, and 13 ml (0.23 mole) of acetic acid were charged to the reaction vessel.
The mixture was heated to reflux, 121° C., and after 8 hours at reflux the reaction was determined to be complete via gas chromatography.
The reaction mass was cooled to room temperature and 20 ml of 1-butanol were added to thin the reaction mixture.
The same procedure as that described in Example 1 was used to isolate and dry thiabendazole.
The weight of dry thiabendazole crystals was 37.92 g, which corresponds to a 75.4percent yield.
The purity was determined to be 99.73percent (based on area percent) using HPLC analysis.
Reference: [1] Patent: US5310923, 1994, A,
[2] Patent: US5310923, 1994, A,
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  • [ 39145-59-0 ]
  • [ 95-54-5 ]
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  • [ 148-79-8 ]
YieldReaction ConditionsOperation in experiment
91.7% With hydrogenchloride; ethylenediaminetetraacetic acid In methanol; water EXAMPLE 5
Preparation of Thiabendazole in Water with Dropwise Addition of 4-Cyanothiazole Dissolved in Methanol, Which is Distilled Off During Addition
To a 500 ml four-neck, round-bottom flask fitted with a mechanical stirrer, condenser, thermometer and pH probe were charged 100 ml of deionized water, 0.1 grams (3.4*10-4 mole) of EDTA and 0.1 grams (5.7*10-4 mole) ascorbic acid.
The reaction vessel was purged with nitrogen and then nitrogen blanketed for the duration of the reaction.
The aqueous solution containing EDTA and ascorbic acid was heated using an oil bath.
When the solution temperature reached 95° C., 54 grams (0.5 mole) of o-phenylenediamine were charged, followed by, dropwise addition of 16 ml concentrated hydrochloric acid (corresponding to 38percent hydrogen chloride) to adjust the pH to a value of 4.0.
Subsequently, 55 grams (0.5 mole) of 4-cyanothiazole were dissolved in 100 ml of methanol and added dropwise over 2 hours to the aqueous solution of o-phenylenediamine monohydrochloride.
Methanol was distilled out of the reaction vessel via a take off condenser during addition.
The reaction mixture was heated to reflux and after 50 min at reflux 50 ml of deionized water was added.
The reaction mixture was held at reflux (103°-104° C.) for a period of 3 hours.
During this time, the pH was maintained at approximately 4.0 (+/-0.2) by periodic addition of 38percent HCl solution.
An additional 25.5 ml of 38percent HCl solution was added to the reaction mixture during the course of the reaction.
The reaction mass was allowed to cool to 50° C. before being vacuum filtered using a medium fritted glass filter.
The same procedure as that described in Example 1 was carried out for washing and drying of thiabendazole.
A total of 92.20 grams of thiabendazole were obtained which corresponds to a 91.7percent yield. HPLC analysis showed that the purity was 98.80percent (based on percent area).
Reference: [1] Patent: US5310924, 1994, A,
[2] Patent: US5310924, 1994, A,
  • 37
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  • [ 50-81-7 ]
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YieldReaction ConditionsOperation in experiment
92.7% With hydrogenchloride; ethylenediaminetetraacetic acid In water EXAMPLE 9
Preparation of Thiabendazole in Water Using Inverse Addition
The same procedure as that described in Example 1 was carried out with the exception that 54 grams (0.5 mole) of o-phenylenediamine were dissolved in 100 ml of deionized water and adjusted to a pH of 4.0 at room temperature using 28 ml of concentrated hydrochloric acid (corresponding to 38percent hydrogen chloride).
The resulting solution was added dropwise over 2 hours to the reaction vessel containing a solution at 95° C. comprising 100 ml of deionized water, 0.1 gram (3.4*10-4 mole) of EDTA, 0.1 gram (5.7*10-4 mole) of ascorbic acid and 55 grams (0.5 mole) of 4-cyanothiazole.
Following this, the reaction mixture was refluxed (103°-104° C.) for 7 hours.
During this time the reaction mixture was maintained at a pH of approximately 4.0 (+/-0.2) by addition of 38percent HCl solution.
An additional 13.5 ml of 38percent HCl solution was added to the reaction mixture during the course of the reaction.
The same procedure as that described in Example 5 was carried out for filtration, washing and drying of thiabendazole.
A total of 93.22 grams of thiabendazole were obtained which corresponds to a 92.7percent yield. HPLC analysis showed that the purity was 98.64percent (based on percent area).
Reference: [1] Patent: US5310924, 1994, A,
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  • [ 1452-15-9 ]
  • [ 5329-14-6 ]
  • [ 95-54-5 ]
  • [ 50-81-7 ]
  • [ 71-36-3 ]
  • [ 148-79-8 ]
Reference: [1] Patent: US5310923, 1994, A,
  • 39
  • [ 1452-15-9 ]
  • [ 95-54-5 ]
  • [ 50-81-7 ]
  • [ 71-36-3 ]
  • [ 148-79-8 ]
Reference: [1] Patent: US5310923, 1994, A,
  • 40
  • [ 72-19-5 ]
  • [ 50-81-7 ]
  • [ 123-32-0 ]
  • [ 13925-00-3 ]
  • [ 13238-84-1 ]
  • [ 13360-65-1 ]
  • [ 13925-03-6 ]
  • [ 18138-05-1 ]
  • [ 13360-64-0 ]
  • [ 15707-34-3 ]
  • [ 15707-23-0 ]
  • [ 18138-04-0 ]
Reference: [1] Food Chemistry, 2010, vol. 119, # 1, p. 214 - 219
  • 41
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  • [ 13925-00-3 ]
  • [ 13238-84-1 ]
  • [ 13360-65-1 ]
  • [ 1115-11-3 ]
  • [ 13925-03-6 ]
  • [ 18138-05-1 ]
  • [ 13360-64-0 ]
  • [ 15707-34-3 ]
  • [ 15707-23-0 ]
  • [ 18138-04-0 ]
Reference: [1] Food Chemistry, 2010, vol. 119, # 1, p. 214 - 219
  • 42
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  • [ 1192-62-7 ]
  • [ 930-68-7 ]
  • [ 3188-00-9 ]
  • [ 10493-98-8 ]
  • [ 23033-96-7 ]
  • [ 431-03-8 ]
Reference: [1] Carbohydrate Research, 1997, vol. 305, # 1, p. 1 - 15
  • 43
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  • [ 98-01-1 ]
  • [ 609-06-3 ]
  • [ 124-38-9 ]
Reference: [1] Bulletin de la Societe Chimique de France, 1959, p. 74,75
[2] Bulletin de la Societe Chimique de France, 1959, p. 74,75
[3] Food Research, 1953, vol. 18, p. 633
  • 44
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  • [ 625-99-0 ]
  • [ 64-19-7 ]
  • [ 490-83-5 ]
Reference: [1] Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 1983, vol. 22, # 3, p. 292 - 294
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  • [ 431-03-8 ]
Reference: [1] Carbohydrate Research, 1997, vol. 305, # 1, p. 1 - 15
  • 46
  • [ 10016-20-3 ]
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  • [ 129499-78-1 ]
Reference: [1] Agricultural and Biological Chemistry, 1991, vol. 55, # 7, p. 1751 - 1756
[2] ACS Catalysis, 2016, vol. 6, # 3, p. 1606 - 1615
  • 47
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YieldReaction ConditionsOperation in experiment
39%
Stage #1: With Geobacillus stearothermophilus Tc-62 cyclomaltodextrin glucanotransferase In water at 55℃; for 50 h; Enzymatic reaction
Stage #2: With glucoamylase GLUCZYM AF6 In water for 24 h; Enzymatic reaction
Test samples 10 to 15, having mutually different purities of ascorbic acid 2-glucoside as shown in Table 3, were prepared from an aqueous solution containing L-ascorbic acid and dextrin. Four parts by weight of "PINEDEX 100", a product name of a dextrin commercialized by Matsutani Chemical Industries Co., Ltd., Hyogo, Japan, was dissolved in 15 parts by weight of water by heating. Then, three parts by weight of L-ascorbic acid was admixed with the solution. Successively, the solution was admixed with 100 units/g dextrin, d.s.b., of a CGTase derived from Geobacillus stearothermophilus Tc-62 strain and 250 units/g dextrin, d.s.b., of an isoamylase specimen, commercialized by Hayashibara Biochemical Laboratories, Inc., Okayama, Japan, and subjected to an enzymatic reaction while keeping the solution at a pH of 5.5 and a temperature of 55°C for 50 hours to form ascorbic acid 2-glucoside. In addition, it can be speculated that α-glycosyl-L-ascorbic acids such as 2-O-α-maltosyl-L-ascorbic acid, 2-O-a-maltotriosyl-L-ascorbic acid, 2-O-α-maltotetraosyl-L-ascorbic acid, etc., would have been naturally formed in the reaction solution. After inactivating the remaining enzymes by heating, the reaction solution was adjusted to pH 4.5, admixed with 50 units/g dextrin, d.s.b., of "GLUCZYM AF6", a product name of a glucoamylase specimen commercialized by Amano Enzymes Inc., Aichi, Japan, and subjected to an enzymatic reaction for 24 hours for hydrolyzing the above α-glycosyl-L-ascorbic acids up to ascorbic acid 2-glucoside and hydrolyzing the remaining concomitant oligosaccharides up to D-glucose. At this stage, the reaction solution contained ascorbic acid 2-glucoside in a production yield of 39percent. The reaction solution was heated to inactivate glucoamylase, decolored with an activated charcoal, filtered, subjected to a column of a cation-exchange resin (H+-form) for desalting, and then subjected to an anion-exchange resin (OH--form) to absorb L-ascorbic acid and ascorbic acid 2-glucoside, followed by washing the resin with water to remove D-glucose and feeding 0.5 N hydrochloric acid solution to effect elution. The eluate was concentrated to give a solid content of about 50percent and then subjected to a column chromatography using "DOWEX 50WX4" (Ca2+-form), a product name of a strong-acid cation exchange resin commercialized by Dow Chemical Company. The concentrate was loaded on the column in a volume of about 1/50-fold of the wet resin volume, followed by feeding to the column refined water in a volume of 50-folds of the load volume of the concentrate at a linear velocity of 1 m/hour and fractionating the resulting eluate by 0.05-volume aliquots of the column volume. Thereafter, the composition of each fraction was measured on HPLC described in Experiment 1-2, and six fractions with an ascorbic acid 2-glucoside content of at least 80percent, d.s.b., were concentrated in vacuo to give respective solid concentrations of about 76percent. The resulting concentrates were respectively placed in a crystallizer, admixed with Test sample 1 in Experiment 1-1, as a seed crystal, in a content of two percent of each of the solid contents, d.s.b., followed by unforcedly cooling each concentrate from 40°C to 15°C over about two days while stirring gently to precipitate anhydrous crystalline ascorbic acid 2-glucoside.
Reference: [1] Patent: EP2653475, 2013, A1, . Location in patent: Paragraph 0125; 0126; 0127; 0128
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Reference: [1] ChemBioChem, 2017, vol. 18, # 14, p. 1387 - 1390
  • 49
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Reference: [1] Journal of Molecular Catalysis B: Enzymatic, 2011, vol. 68, # 3-4, p. 223 - 229
  • 50
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  • [ 86404-04-8 ]
YieldReaction ConditionsOperation in experiment
69% With potassium carbonate In N,N-dimethyl-formamide at 20℃; Example 7: Preparation of L-?-?-lipoyl-3-ethyl-ascorbic acid8.15 g of L-3-ethyl-ascorbic acid (yield: 87 percent) was prepared in the same manner as in Step 1 of Example 5, except that 5.00 g of bromo ethane was used instead of polyethylene glycol bromide. Example 10: Preparation of L-2-?-lipoyl-3-ethyl-ascorbic acid. Step 1. Preparation of L-3-polyethylene glycol-ascorbic acid 5.O g of bromo ethane and 0.97 g of ascorbic acid were added to 30 ml of dimethylformamide. 0.98 g of potassium carbonate was added to the reaction mixture, which was then stirred at room temperature overnight. The resultant was distilled under reduced pressure, and 100 ml of ethyl acetate was added to the resulting residue. The resultant was washed three times with 1 N hydrochloric acid and water. The resultant was distilled under reduced pressure to remove the solvent and dried in vacuo to obtain 4.06 g of L-3-ethyl-ascorbic acid (yield: 69percent).
Reference: [1] Patent: WO2009/14343, 2009, A2, . Location in patent: Page/Page column 21; 23
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Reference: [1] Heterocycles, 2005, vol. 66, # 1, p. 579 - 582
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Reference: [1] Heterocycles, 2005, vol. 66, # 1, p. 579 - 582
  • 53
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  • [ 50709-35-8 ]
YieldReaction ConditionsOperation in experiment
71% With sodium nitrite In hydrogenchloride; water EXAMPLE 8
Preparation of 2,5-dichlorophenylhydrazine Hydrochloride
Concentrated HCl (120 ml, 32percent, 1.2 moles) was charged to a 500 ml flask under a nitrogen atmosphere and cooled down to -2 to 0° C. 2,5-Dichloroaniline (20 g, 123 mmoles) was added in one portion as a solid.
The reaction mixture was re-cooled to -2 to 0° C. and sodium nitrite (10.2 g, 0.148 moles) dissolved in water (20 ml) was added dropwise to the acidic solution through an addition funnel over a period of 1 hour at -2 to 0° C.
The resulting mixture was stirred for 1 hour at -2 to 0° C. L-Ascorbic acid (22.8 g, 0.129 moles) was then added portionwise as a solid over a period of 1 hour at -2 to 0° C.
The reaction was allowed to come to room temperature (18-20° C.) over a period of 10 minutes, then heated at 40° C. and stirred for 2 hours at this temperature.
The resultant slurry was cooled to room temperature (18-20° C.) and water (50 ml) was added.
The mixture was stirred 16 hours at 20-25° C., then filtered and the solid was washed with water to afford 110 g of wet oxalic acid intermediate.
One hundred eight grams of wet oxalic acid intermediate product were suspended in concentrated HCl (160 ml) and water (90 ml) and stirred at 90° C. for 2 hours.
The orange suspension was cooled and stirred for 16 hours at 20-25° C.
The solid was filtered and dried to constant weight, resulting in 22.4 g of 2,5-dichlorophenylhydrazine.HCl.xH2O (x=2-3) as an orange solid (HPLC purity calculated as area percent:
98.3percent; 71percent overall molar yield based on a molecular weight of 260.34 for 2,5-dichlorophenylhydrazine monohydrochloride with 2.6 molecules of crystallization water).
Reference: [1] Patent: US2002/82274, 2002, A1,
  • 54
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  • [ 70753-61-6 ]
YieldReaction ConditionsOperation in experiment
94.6%
Stage #1: With calcium carbonate In water at 0 - 5℃;
Stage #2: With dihydrogen peroxide In water at 5 - 75℃; for 18 h;
Stage #3: With methanol In water at 20 - 50℃; for 12 h;
L-Ascorbic acid (52.8 g, 0.3 mol) was dissolved in water (410 mL). To the solution was added calcium carbonate (60.06 g, 0.6 mol) and the slurry was cooled to 05° C. Hydrogen peroxide (50percent w/w, 61.2 ml, 0.9 mol) was added dropwise at 520° C. over a period of 60 minutes, and the mixture was then stirred at room temperature for sixteen hours. The reaction mixture was heated at 7075° C. for one hour until no more oxygen was evolved. The suspension was filtered at 7075° C., and the filter cake was washed with 50-60° C. hot water (30 mL.x.2). The combined filtrate was concentrated to about 20 mL at 55° C. under reduced pressure. Methanol (250 ml) was added dropwise to the warm concentrate (about 50° C.) until the solution became cloudy, and the mixture was then stirred at room temperature for twelve hours, filtered, and the precipitate was washed with methanol (30 mL.x.3). The solid was dried to a constant weight at 60° C. (3 hours) to give 45.2 grams (Yield: 94.6percent) of Calcium L-threonate (Bock et al. Acta Chem. Scand. Ser. B, 37, 342-344 (1983)). IR (KBr) 1600 (s) cm-1; 1H-NMR (D2O, 400 MHz): δ4.02 (2 1H, Hc, Jbc=2.3 Hz), 3.94 (ddd, 1H, Hb, Jab=7.7 Hz, Ja'b=5.2 Hz, Jbc=2.2 Hz), 3.65 (ABX, 1H, Ha', Jaa'=11.6 Hz, Ja'b=5.2 Hz), 3.58 (ABX, 1H, Ha, Jaa'=11.6 Hz, Jab=7.7 Hz).
61% With dihydrogen peroxide; calcium carbonate In water at 12 - 20℃; for 24 h; This compound was synthesized according to a known procedure (Schoning, K. U.; Scholz, P.; Wu, X. L.; Guntha, S.; Delgado, G.; Krishnamurthy, R.; Eschenmoser, A. Helv. Chim. Acta 2002, 85, 4111). To a solution of 200 g (1.14 mol) of L-ascorbic acid dissolved in 1.6 L of distilled water, 227 g (2.27 mol) of CaCO3 was slowly added with stirring, and the slurry was cooled to 15°C. To this mixture, 455 ml of 30percent aq. H2O2 solution was added, at 12-18°C, over a period of 6 hours, and the mixture was stirred at room temperature for 18 hours. The mixture, under constant stirring, was treated with 45 g of charcoal and heated to 70°C, stirred for 3 hours. The hot suspension was filtered, and the solid washed with 2 × 38 ml of distilled water. The washings were combined with the filtrate and concentrated to 1.52 L under reduced pressure. The resulting solution was stirred, and 455 ml of MeOH was slowly added over a period of 5 hours. After stirring for 5 hours, another 455 ml of MeOH was slowly added. The solids were isolated by filtration, washed with 2 × 100 ml of MeOH, and dried under reduced pressure to constant weight. The combined filtrates were concentrated, MeOH was slowly added, and the resulting precipitate was isolated by filtration. The procedure was repeated, and the first two crops gave 107.8 g (61percent) of 1a as a colourless powder.
Reference: [1] Canadian Journal of Chemistry, 2003, vol. 81, # 8, p. 937 - 960
[2] Patent: US2003/232820, 2003, A1, . Location in patent: Page 16
[3] Journal of Organic Chemistry, 2016, vol. 81, # 6, p. 2302 - 2307
[4] Journal of Organic Chemistry, 1985, vol. 50, # 19, p. 3462 - 3467
[5] Helvetica Chimica Acta, 2002, vol. 85, # 12, p. 4111 - 4153
[6] Patent: WO2016/174081, 2016, A1, . Location in patent: Page/Page column 20; 21
[7] Organic Letters, 2006, vol. 8, # 25, p. 5809 - 5811
[8] Patent: US2017/106016, 2017, A1, . Location in patent: Paragraph 0194
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