* 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.
With borane-THF; In tetrahydrofuran; at 0 - 20℃; for 3h;Inert atmosphere;
To a solution of 3-methyl-4-nitro-benzoic acid (2 g, 11.04 mmol, 1 eq) in anhydrous THF (20 mL) was added BH3-THF (1 M, 27.60 mL, 2.5 eq) at 0-5 C. under N2 atmosphere. The mixture was stirred at 20 C. for 3 h. The reaction mixture was quenched by addition of MeOH (30 mL) at 20 C. then stirred at 20 C. for 0.5 h. The mixture was concentrated to afford the crude product (3-methyl-4-nitro-phenyl)methanol (1.66 g, 9.93 mmol, 89.9% yield, 100% purity) as an off-white solid which was used in the next step without further purification. 1H NMR (400 MHz, CD3OD) δ ppm 7.97 (d, J=8.3 Hz, 1H), 7.46-7.35 (m, 2H), 4.90 (s, 2H), 2.59 (s, 3H); ES-LCMS m/z 168.2 [M+H]+.
67 g
With Trimethyl borate; dimethylsulfide borane complex; In tetrahydrofuran; methanol; dichloromethane; at 65℃; for 6h;Inert atmosphere;
A flask purged with nitrogen was charged with 3-methyl-4-nitro-benzoic acid (72.5 g, 0.400 mol), trimethyl borate (166.2 g, 1.600 mol) and dry tetrahydrofuran (1449 mL). A solution of borane dimethyl sulfide complex (63.8 g, 79.8 mL, 0.840 mol) was added drop-wise to the stirred batch at 20-35 C. over at least 30 min. An exotherm and effervescence were observed during the addition. The mixture was stirred at 65 C. for at least 6 h or until in-process HPLC analysis showed that conversion was greater than 97%. Reaction was quenched at 20-40 C. with cooling by drop-wise addition of methanol (46 mL) followed by aq 5 N hydrochloric acid (144 mL) over at least 30 min. Exotherm and effervescence were observed during the quench. After stirring the batch at 50 C. for at least 1 h, it was concentrated under reduced pressure to a volume of 360 mL. The concentrated batch was washed with water (453 mL) and the solids were collected on a filter. The wet filter cake was dissolved in CH2Cl2 (2170 mL) at and the resulting solution dried over anhydrous magnesium sulfate (36 g). The dried filtrate solution containing the title compound (67 g, 100% yield) was used directly in the preparation of 3-methyl-4-nitro-benzaldehyde.
Adding a time fresh material of the oxidation reactor 2,4-dimethyl-nitrobenzene and catalyst is dissolved in the acetic acid CeO2, naphthenic acid cobalt and having the general formula (IV) of a metal phthalocyanine structure (R1=H, R2=CH3CH2, M=Mn) mixture, the total concentration of 450 ppm, acetic acid and 2,4-dimethylnitro Benzene mass ratio of 0. 08. When the device was operated stably, the flow rate of the fresh material in the oxidation reactor was 6.0 mL / h. The average residence time of the oxidation reactor in liquid phase was 5.0 h, and the mass fraction of oxygen was 80% oxygen-enriched air was continuously fed into the oxidation reactor, maintaining the reaction temperature at 125 C and the reaction pressure at 0.6 MPa. The volume ratio of the water added into the hydrolysis reactor to the oxidation reaction liquid entering the hydrolysis reactor is 0.43: 1, and the oxygen-enriched air with the oxygen mass percentage of 80% is continuously fed, and the reaction temperature in the hydrolysis reactor is maintained at 78 C, the reaction pressure is 0. 4MPa, then the hydrolysis reactor liquid phase residence time of 5. Oh. Hydrolysis reactor out The liquid-liquid phase was continuously fed into the liquid-liquid delaminator at a temperature of 45. 8 C and a pressure of 0.3 MPa. The conversion of 2,4-dimethylnitrobenzene in the system was 97.0%, The selectivities of 3-methyl-4-nitrobenzyl alcohol, 3-methyl-4-nitrobenzaldehyde and 3-methyl-4-nitrobenzoic acid were 54.2%, 36.5% 9.3%, other by-products were not detected.
4-methyl-5-acetyl-2-(3-methyl-4-nitrobenzoylamino)thiazole[ No CAS ]
Yield
Reaction Conditions
Operation in experiment
44%
6.0mmol benzoic acid was dissolved in 10mL DMF solution,0.972 g (6.0 mmol) of N,N'-carbonyldiimidazole (CDI) was added in portions.Stir at room temperature for 30 min,4.0 mmol of 4-methyl-5-acetyl-2-aminothiazole was added and reacted at 85 C for 8 h.After cooling to room temperature, the reaction solution was poured into 30 mL of ice water to precipitate a large amount of solid.The crude product was recrystallized from ethyl acetate / THF to yield white solid4-methyl-5-acetyl-2-benzoylaminothiazole, yield 61.0%
Chemistry
Pharmaceutical Intermediates
Inhibitors/Agonists
Material Science
For Research Only
120K+ Compounds
Competitive Price
1-2 Day Shipping
