[ CAS No. 671802-00-9 ] {[proInfo.proName]}

Name: 671802-00-9|tert-Butyl 3-(2-hydroxyethoxy)propanoate|98%
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Quality Control of [ 671802-00-9 ]

COA NMR CNMR HPLC LC-MS

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SDS Specification

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Product Details of [ 671802-00-9 ]

CAS No. :	671802-00-9	MDL No. :	MFCD22056310
Formula :	C₉H₁₈O₄	Boiling Point :	-
Linear Structure Formula :	-	InChI Key :	ACWLDITVZGWIKA-UHFFFAOYSA-N
M.W :	190.24	Pubchem ID :	11263965
Synonyms :		Chemical Name :	tert-Butyl 3-(2-hydroxyethoxy)propanoate

Safety of [ 671802-00-9 ]

Signal Word:	Warning	Class:	N/A
Precautionary Statements:	P261-P305+P351+P338	UN#:	N/A
Hazard Statements:	H315-H319-H335	Packing Group:	N/A
GHS Pictogram:

Application In Synthesis of [ 671802-00-9 ]

* 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 [ 671802-00-9 ]
Downstream synthetic route of [ 671802-00-9 ]

[ 671802-00-9 ] Synthesis Path-Upstream 1~1

1
[ 1663-39-4 ]
[ 107-21-1 ]
[ 671802-00-9 ]

Yield	Reaction Conditions	Operation in experiment
24%	With sodium In tetrahydrofuran at 20℃; for 24 h;	To a solution of ethylene glycol 16-1 (13.1 mL, 235 mmol) in 100 mL of tetrahedrofuran was added 47 mg of sodium. 12 mL of tert-butylacrylate was added after sodium was dissolved. The reaction mixture was stirred at room temperature for 24 hours. The reaction mixture was concentrated in vacuo and quenched with 2 mL of 1 N HCl. The residue was suspended in brine and extracted with ethyl acetate (100 mLXl, 50 mL X2). The organic layer was combined and washed with brine, dried over sodium sulfate and concentrated in vacuo. The residue was purified by flash column chromatography to give 5.2 g (24percent) of compound 16-3.
24%	With sodium In tetrahydrofuran at 20℃; for 24 h;	Compound 16-3: To a solution of ethylene glycol 16-1 (13.1 mL, 235 mmol) in100 rn.L of tetrahedrofuran was added 47 mg of sodium. 12 mL of tert-butylacrylate wasadded after sodimn was dissolved. The reaction rnixtme was stirred at room temperature for5 24 hours. The reaction mixture was concentrated in vacuo and quenched with 2 mL of 1 NHCI. The residue was suspended in brine and extracted with ethyl acetate (100 mLX1, 50 mLX2). The organic layer was combined and washed with brine, dried over sodium sulfate andconcentrated in vacuo. The residue was purified by flash column chromatography to give 5.2g (24percent) of compound 16-3.
24%	With sodium In tetrahydrofuran at 20℃; for 24 h;	To a solution of ethylene glycol16-1 (13. 1 mL, 235 mmol) in 100 mLoftetrahedrofuran was added 47 mg of sodium. 12 mL oftert-butylacrylate was added after sodiumwas dissolved. The reaction mixture was stirred at room temperature for 24 hours. The reaction5 mixture was concentrated in vacuo and quenched with 2 mL of 1 N HCl. The residue was suspendedin brine and extracted with ethyl acetate (1 00 mLXl, 50 mL X2). The organic layer was combinedand washed with brine, dried over sodium sulfate and concentrated in vacuo. The residue waspurified by flash column chromatography to give 5.2 g (24percent) of compmmd 16-3.

22%

at 20℃; for 96 h;

tert-Butyl acrylate (5.72 mL, 39.0 mmol) was added to a mixture of ethylene glycol (2.42 g, 39.0 mmol), tetrabutylammonium bromide (377 mg, 1.17 mmol) and potassium hydroxide (77 mg; purity, 85percent; 1.17 mmol), and the mixture was stirred at room temperature for 4 days. The reaction mixture was purified by silica gel column chromatography (hexane:ethyl acetate = 4:1 --> 2: 1, v/v) to give the title compound (1.66 g; yield, 22percent) as a colorless oily substance. ¹H NMR (CDCl₃, 400 MHz): δ 1.47 (9H, s), 2.44 (1H, brs), 2.52 (2H, t, J = 6.1 Hz), 3.59 (2H, t, J = 5.6 Hz), 3.73-3.76 (4H, m).

Reference： [1] Patent: WO2012/166560, 2012, A1, . Location in patent: Page/Page column 171-172
[2] Patent: WO2013/192360, 2013, A1, . Location in patent: Paragraph 00490
[3] Patent: WO2013/185117, 2013, A1, . Location in patent: Paragraph 00476
[4] Patent: EP2409977, 2012, A1, . Location in patent: Page/Page column 66
[5] Synthetic Communications, 2004, vol. 34, # 13, p. 2425 - 2432
[6] Synthetic Communications, 2007, vol. 37, # 11, p. 1899 - 1915
[7] Patent: US2005/36978, 2005, A1, . Location in patent: Page/Page column 23

[ 671802-00-9 ] Synthesis Path-Downstream 1~57

1
[ 1663-39-4 ]
[ 107-21-1 ]
[ 671802-00-9 ]

Yield	Reaction Conditions	Operation in experiment
24%	With sodium; In tetrahydrofuran; at 20℃; for 24h;	To a solution of ethylene glycol 16-1 (13.1 mL, 235 mmol) in 100 mL of tetrahedrofuran was added 47 mg of sodium. 12 mL of tert-butylacrylate was added after sodium was dissolved. The reaction mixture was stirred at room temperature for 24 hours. The reaction mixture was concentrated in vacuo and quenched with 2 mL of 1 N HCl. The residue was suspended in brine and extracted with ethyl acetate (100 mLXl, 50 mL X2). The organic layer was combined and washed with brine, dried over sodium sulfate and concentrated in vacuo. The residue was purified by flash column chromatography to give 5.2 g (24%) of compound 16-3.
24%	With sodium; In tetrahydrofuran; at 20℃; for 24h;	Compound 16-3: To a solution of ethylene glycol 16-1 (13.1 mL, 235 mmol) in100 rn.L of tetrahedrofuran was added 47 mg of sodium. 12 mL of tert-butylacrylate wasadded after sodimn was dissolved. The reaction rnixtme was stirred at room temperature for5 24 hours. The reaction mixture was concentrated in vacuo and quenched with 2 mL of 1 NHCI. The residue was suspended in brine and extracted with ethyl acetate (100 mLX1, 50 mLX2). The organic layer was combined and washed with brine, dried over sodium sulfate andconcentrated in vacuo. The residue was purified by flash column chromatography to give 5.2g (24%) of compound 16-3.
24%	With sodium; In tetrahydrofuran; at 20℃; for 24h;	To a solution of ethylene glycol16-1 (13. 1 mL, 235 mmol) in 100 mLoftetrahedrofuran was added 47 mg of sodium. 12 mL oftert-butylacrylate was added after sodiumwas dissolved. The reaction mixture was stirred at room temperature for 24 hours. The reaction5 mixture was concentrated in vacuo and quenched with 2 mL of 1 N HCl. The residue was suspendedin brine and extracted with ethyl acetate (1 00 mLXl, 50 mL X2). The organic layer was combinedand washed with brine, dried over sodium sulfate and concentrated in vacuo. The residue waspurified by flash column chromatography to give 5.2 g (24%) of compmmd 16-3.

22%	With tetrabutylammomium bromide; potassium hydroxide; at 20℃; for 96h;	tert-Butyl acrylate (5.72 mL, 39.0 mmol) was added to a mixture of ethylene glycol (2.42 g, 39.0 mmol), tetrabutylammonium bromide (377 mg, 1.17 mmol) and potassium hydroxide (77 mg; purity, 85%; 1.17 mmol), and the mixture was stirred at room temperature for 4 days. The reaction mixture was purified by silica gel column chromatography (hexane:ethyl acetate = 4:1 ? 2: 1, v/v) to give the title compound (1.66 g; yield, 22%) as a colorless oily substance. 1H NMR (CDCl3, 400 MHz): delta 1.47 (9H, s), 2.44 (1H, brs), 2.52 (2H, t, J = 6.1 Hz), 3.59 (2H, t, J = 5.6 Hz), 3.73-3.76 (4H, m).
6.9%		To a solution of ethylene glycol (5.0 mL) in THF (100 mL) was added sodium hydride (0.19 g, 4.7 mmol) at 0 C., and then the reaction mixture was stirred warming to room temperature for 30 minutes. To the reaction mixture at 0 C. was added a solution of tert-butyl acrylate (2 g, 16 mmol) in THF (50 mL) over 30 minutes, and the mixture was stirred at room temperature for 2 days, and concentrated in vacuo. The obtained residue was purified by silica gel column chromatography (pentane:ethyl acetate=3:1-1:1) to give Compound (g-2) (0.34 g, 6.9% yield). (1086) 1H-NMR (CDCl3, 400 MHz) delta: 4.21-4.20 (m, 2H), 3.87-3.82 (m, 1H), 3.75-3.70 (m, 2H), 3.59-3.56 (m, 2H), 2.52-2.49 (m, 2H), 1.46 (s, 9H).
	With potassium hydroxide; tetrabutylammomium bromide; at 20℃;	Tert-butyl acrylate (130 g, 1.01 mole) was added dropwise over 3 hours to a mixture of anhydrous ethylene glycol (62 g, 1.0 mole), tetrabutylammonium bromide (9.6 g) and KOH (powder, 2.2 g), and stirred overnight at room temperature under an argon atmosphere. The volatile products were distilled off under reduced pressure (rotoevaporator, 60 C.) and the mixture was dissolved in 250 ml dichloromethane. The solution was washed with 250 ml of distilled water, dried with anhydrous magnesium sulfate, and the solvent was distilled off under reduced pressure. The product (Compound 2) was then subjected to vacuum distillation (kugelrohr, t=95-100 C., 0.05 mm Hg). Yield 36.6 g. NMR (d6-DMSO): 1.40 ppm (s, 9H), 2.42 ppm (t, 2H), 3.39 ppm (m, 2H), 3.46 ppm (m, 2H), 3.59 ppm(s, 2H), 4.55 ppm (t, 1H).
14 g		Ethanediol (7.6 mL, 0.15 mol) was dissolved in 100 mL dry THF, 100 mg metal sodium was added, the reaction mixture was stirred at room temperature till the metal sodium was completely consumed, tert-butyl acrylate (14.5 mL, 0.1 mol) was added, then the mixture was stirred overnight at room temperature. THF was removed under reduced pressure, 100 mL EtOAc was added to the residue, the mixture was washed with water for 3 times (50 mL×3), dried over anhydrous sodium sulfate, concentrated, the crude product was purified by silica gel column chromatography (PE/EtOAc=1:1) to give 14 g product 2-22 as colorless oil, yield 73%. LCMS (ESI) m/z 191.1 (M+H)+.

Reference： [1]ACS Medicinal Chemistry Letters,2019,vol. 10,p. 767 - 772
[2]Journal of the American Chemical Society,2018,vol. 140,p. 17019 - 17026
[3]Patent: WO2012/166560,2012,A1 .Location in patent: Page/Page column 171-172
[4]Patent: WO2013/192360,2013,A1 .Location in patent: Paragraph 00490
[5]Patent: WO2013/185117,2013,A1 .Location in patent: Paragraph 00476
[6]Patent: EP2409977,2012,A1 .Location in patent: Page/Page column 66
[7]Synthetic Communications,2004,vol. 34,p. 2425 - 2432
[8]European Journal of Organic Chemistry,2019,vol. 2019,p. 5409 - 5423
[9]Patent: US2019/16711,2019,A1 .Location in patent: Paragraph 1084-1086
[10]Synthetic Communications,2007,vol. 37,p. 1899 - 1915
[11]Patent: US2005/36978,2005,A1 .Location in patent: Page/Page column 23
[12]Patent: US10449258,2019,B2 .Location in patent: Page/Page column 203; 204

2
[ 822-06-0 ]
[ 671802-00-9 ]
C₁₇H₃₀N₂O₆ [ No CAS ]

Reference： [1]Synthetic Communications,2007,vol. 37,p. 1899 - 1915

3
[ 108-24-7 ]
[ 671802-00-9 ]
[ 671802-01-0 ]

Yield	Reaction Conditions	Operation in experiment
	With pyridine; dmap; at 20℃;	A mixture of Compound 2 (36.6 g, 0.19 moles), pyridine (52 ml, 0.64 moles), acetic anhydride (52 ml, 0.55 moles) and dimethylaminopyridine (DMAP, 1.0 g) was stirred overnight at room temperature. The volatile products were then distilled off under reduced pressure (rotoevaporator, t=65 C.) and the product (Compound 3) was subjected to vacuum distillation (kugelrohr, 100-110 C., 0.05 mm Hg). Yield 40.9 g. NMR (d6-DMSO): 1.40 ppm (s, 9H), 2.02 ppm (s, 3H), 2.42 ppm (t, 2H), 3.58 ppm (bm, 4H), 4.08 ppm (m, 2H).

Reference： [1]Patent: US2005/36978,2005,A1 .Location in patent: Page/Page column 23-24

4
[ 104-15-4 ]
[ 671802-00-9 ]
[ 1309666-78-1 ]

Reference： [1]Chemistry - A European Journal,2011,vol. 17,p. 5344 - 5349

5
[ 671802-00-9 ]
[ 1309666-79-2 ]

Reference： [1]Chemistry - A European Journal,2011,vol. 17,p. 5344 - 5349

6
[ 671802-00-9 ]
[ 1309666-80-5 ]

Reference： [1]Chemistry - A European Journal,2011,vol. 17,p. 5344 - 5349

7
[ 524-38-9 ]
[ 671802-00-9 ]
[ 1415329-03-1 ]

Yield	Reaction Conditions	Operation in experiment
	With di-isopropyl azodicarboxylate; triphenylphosphine; In tetrahydrofuran; at 0 - 20℃;	Compound 16-3 (2.0 g, 10.5 mmol), N-hydroxyphthalimide (2.05 g, 12.6 mmol) and triphenylphosphine (3.58 g, 13.65 mmol) were dissolved in 50 mL of tetrahydrofuran followed by addition of DIAD (3.26 mL, 15.75 mmol) at 0C. The resulting solution was stirred at room temperature overnight, and then concentrated to dryness. The residue was purified by flash column chromatography to give compound 16-5.
	With di-isopropyl azodicarboxylate; triphenylphosphine; In tetrahydrofuran; at 0 - 20℃;	Compound 16-5: Compound 16-3 (2.0 g, 10.5 mmol), N-hydroxyphthalimide(2.05 g, 12.6 mmol) and triphenylphosphine (3.58 g, 13.65 mmol) were dissolved in 50 mLof tetrahydrofuran followed by addition of DIAD (3.26 mL, 15.75 mmol) at 0C. Theresulting solution was stirred at room temperature overnight, and then concentrated to5 dryness. The residue was purified by flash column chromatography to give compound 16-5.
	With di-isopropyl azodicarboxylate; triphenylphosphine; In tetrahydrofuran; at 0 - 20℃;	Compound 16-3 (2.0 g, 10.5 mmol), N-hydroxyphthalimide (2.05 g,10 12.6 mmol) and triphenylphosphine (3.58 g, 13.65 mmol) were dissolved in 50 mL of tetrahydrofuran followed by addition of DIAD (3.26 mLl 15.75 mmol) at 0C. The resulting solutionwas stirred at room temperature overnight, and then concentrated to dryness. The residue waspurified by flash column chromatography to give compound 16-5.

Reference： [1]Patent: WO2012/166560,2012,A1 .Location in patent: Page/Page column 172
[2]Patent: WO2013/192360,2013,A1 .Location in patent: Paragraph 00491
[3]Patent: WO2013/185117,2013,A1 .Location in patent: Paragraph 00477

8
[ 671802-00-9 ]
[ 1415329-05-3 ]

Reference： [1]Patent: WO2012/166560,2012,A1
[2]Patent: WO2013/192360,2013,A1
[3]Patent: WO2013/185117,2013,A1

9
[ 671802-00-9 ]
[ 1415329-07-5 ]

Reference： [1]Patent: WO2012/166560,2012,A1
[2]Patent: WO2013/192360,2013,A1
[3]Patent: WO2013/185117,2013,A1

10
[ 671802-00-9 ]
C₆₅H₁₀₂N₁₂O₁₄S [ No CAS ]

Reference： [1]Patent: WO2013/185117,2013,A1

11
[ 13466-38-1 ]
[ 671802-00-9 ]
tert-butyl 3-{2-[(5-bromopyridin-2-yl)oxy]ethoxy}propanoate [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
50%	With triphenylphosphine; diethylazodicarboxylate; In tetrahydrofuran; at 20℃;Inert atmosphere;	Step 1: Synthesis of tert-butyl 3-{2-[(5-bromopyridin-2-yl)oxy]ethoxy}propanoate:[0692] To a stirred solution of 5-bromopyridin-2-ol (3.0 g, 17.24 mmol), tert-butyl 3-(2- hydroxyethoxy)propanoate (3.3 g, 17.19 mmol) and triphenylphosphine (6.8 g, 25.81 mmol) in tetrahydrofuran (120.0 mL) was added diethyl diazene-l,2-dicarboxylate (4.49 g, 25.78 mmol) dropwise at 0 C under an atmosphere of nitrogen. The resulting solution was stirred overnight at rt. The reaction mixture was concentrated under reduced pressure to give a crude residue, which was purified by silica gel flash chromatography (eluent: ethyl acetate/petroleum ether, v/v =1/3) to provide the titled product (yield: 50%) as colorless oil.

Reference： [1]Patent: WO2016/118666,2016,A1 .Location in patent: Paragraph 0691; 0692

12
[ 671802-00-9 ]
tert-butyl 3-(2-[5-(4-nitrophenyl)pyridin-2-yl]oxy}ethoxy)propanoate [ No CAS ]

Reference： [1]Patent: WO2016/118666,2016,A1

13
[ 671802-00-9 ]
tert-butyl 3-(2-[5-(4-aminophenyl)pyridin-2-yl]oxy}ethoxy)propanoate [ No CAS ]

Reference： [1]Patent: WO2016/118666,2016,A1

14
[ 5044-52-0 ]
[ 671802-00-9 ]
(2-{2-[3-(tert-butoxy)-3-oxopropoxy]ethoxy}ethyl)triphenylphosphonium bromide [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
0.92 g	With n-butyllithium; In tetrahydrofuran; at 20℃; for 24h;	To a solution of triphenyl(vinyl)phosphonium bromide (1 .62 g, 4.38 mmol) and tert-butyl 3- (2-hydroxyethoxy)propanoate (1.24 g, 6 mmol) in dry THF (15 mL) was added 2.5 M butyllithium (0.18 mL, 0.44 mmol). The resulting reaction was stirred at room temperature. After 24 h the reaction mixture was quenched with MeOH (5 mL) and concentrated under reduced pressure. The resulting residue was purified by chromatography eluting with 0- 10% MeOH/0.7 M NH3in DCM to give (2-{2-[3-(tert-butoxy)-3- oxopropoxy]ethoxy}ethyl)triphenylphosphonium bromide (0.92 g) as a sticky opague oil, which was used in the next step without any further purification.

Reference： [1]Patent: WO2018/193117,2018,A1 .Location in patent: Paragraph 00251

15
[ 671802-00-9 ]
[2-(2-{3-[(2R,3S,4R,5R,8R,10R,11R,12S,13S,14R)-11-[(2S,3R,4S,6R)-4-(dimethylamino)-3-hydroxy-6-methyloxan-2-yl]oxy}-2-ethyl-3,4,10-trihydroxy-13-[(2R,4R,5S,6S)-5-hydroxy-4-methoxy-4,6-dimethyloxan-2-yl]oxy}-3,5,8,10,12,14-hexamethyl-15-oxo-1-oxa-6-azacyclopentadecan-6-yl]-3-oxopropoxy}ethoxy)ethyl]triphenylphosphonium bromide [ No CAS ]

Reference： [1]Patent: WO2018/193117,2018,A1

16
[ 671802-00-9 ]
{2-[2-(2-carboxyethoxy)ethoxy]ethyl}triphenylphosphonium bromide [ No CAS ]

Reference： [1]Patent: WO2018/193117,2018,A1

17
[ 671802-00-9 ]
tert-butyl 3-(2-iodoethoxy)propanoate [ No CAS ]

Reference： [1]Journal of the American Chemical Society,2018,vol. 140,p. 17019 - 17026

18
[ 671802-00-9 ]
tert-butyl 3-(2-(4-((4-((3-(N-methylmethylsulfonamido)benzyl)amino)-5-(trifluoromethyl)pyrimidin-2-yl)amino)phenoxy)ethoxy)propanoate [ No CAS ]

Reference： [1]Journal of the American Chemical Society,2018,vol. 140,p. 17019 - 17026

19
[ 671802-00-9 ]
(2S,4R)-1-((S)-3,3-dimethyl-2-(3-(2-(4-((4-((3-(N-methylmethylsulfonamido)benzyl)amino)-5-(trifluoromethyl)pyrimidin-2-yl)amino)phenoxy)ethoxy)propanamido)butanoyl)-4-hydroxy-N-(4-(4-methylthiazol-5-yl)benzyl)pyrrolidine-2-carboxamide [ No CAS ]

Reference： [1]Journal of the American Chemical Society,2018,vol. 140,p. 17019 - 17026

20
[ 671802-00-9 ]
(2S,4S)-1-((S)-3,3-dimethyl-2-(3-(2-(4-((4-((3-(N-methylmethylsulfonamido)benzyl)amino)-5-(trifluoromethyl)pyrimidin-2-yl)amino)phenoxy)ethoxy)propanamido)butanoyl)-4-hydroxy-N-(4-(4-methylthiazol-5-yl)benzyl)pyrrolidine-2-carboxamide [ No CAS ]

Reference： [1]Journal of the American Chemical Society,2018,vol. 140,p. 17019 - 17026

21
[ 671802-00-9 ]
C₂₅H₂₈F₃N₅O₆S [ No CAS ]

Reference： [1]Journal of the American Chemical Society,2018,vol. 140,p. 17019 - 17026

22
[ 124-63-0 ]
[ 671802-00-9 ]
tert-butyl 3-[2-(methanesulfonyloxy)ethoxy]propanoate [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
100%	With triethylamine; In tetrahydrofuran; at 0 - 20℃; for 16h;	To a solution of Compound (g-2) (0.15 g, 0.79 mmol) and triethylamine (0.16 g, 1.6 mmol) in THF (10 mL) was added methanesulfonyl chloride (0.13 g, 1.2 mmol) at 0 C., and then the reaction mixture was stirred at room temperature for 16 hours. The solvent was removed under reduced pressure, and the residue was dissolved in ethyl acetate (30 mL). The solution was washed with saturated aqueous sodium hydrogencarbonate, dried with sodium sulfate, and concentrated in vacuo to give Compound (g-3) (0.21 g, 100% yield). (1089) 1H-NMR (CDCl3, 400 MHz) delta: 3.68-3.64 (m, 4H), 3.03-2.99 (m, 2H), 2.98 (s, 3H), 2.44-2.41 (m, 2H), 1.38 (s, 9H).
	With triethylamine; In dichloromethane; at 0 - 20℃;	Product 2-22 (7.6 g, 40 mmol) obtained in the previous step and Et3N (6.6 mL, 48 mmol) were dissolved in 50 mL DCM, the mixture was cooled to 0 C., methanesulfonyl chloride (3.5 mL, 44 mmol) was added dropwise slowly. The reaction mixture was warmed to room temperature and stirred for 2 hours. 50 mL Water was added to quench the reaction, the organic phase was separated, washed with saturated brine for 3 times (50 mL×3), dried over anhydrous sodium sulfate, concentrated to give crude product as light yellow oil, which was used directly for the next step. LCMS (ESI) m/z 269.1 (M+H)+.

Reference： [1]Patent: US2019/16711,2019,A1 .Location in patent: Paragraph 1087-1089
[2]Patent: US10449258,2019,B2 .Location in patent: Page/Page column 203; 205

23
[ 671802-00-9 ]
3-[2-([3-(6,7-dihydroxy-1-methyl-4-oxo-1,4-dihydroquinolin-3-yl)-6,7-dihydroxy-4-oxo-4H-chromen-5-yl]carbonyl}oxy)ethoxy]propanoic acid [ No CAS ]