تفاعل #2286377

معادلة التفاعل

Water

HCl

2-pyridin-3-yl-4-trifluoromethyl-thiazole-5-carboxylic acid ethyl ester

sodium hydroxide

→

desired product

المردود 58.4%

2-pyridin-3-yl-4-trifluoromethyl-thiazole-5-carboxylic acid

المردود 58.4%

المذيبات

methanol

ظروف التفاعل

المعالجة

1. 1
   أخرىa precipitate was formed
2. 2
   ترشيحthe heterogeneous mixture was filtered under reduced pressure
3. 3
   غسيلThe precipitate was rinsed further with water
4. 4
   أخرىdried in vacuo

الإجراء التجريبي

To a solution of 2-pyridin-3-yl-4-trifluoromethyl-thiazole-5-carboxylic acid ethyl ester (13.9 g, 46 mmol, ca. 85% pure) in methanol (150 mL) was added an aqueous solution of sodium hydroxide (total volume 75 mL, 140 mmol), and the mixture was stirred for 40 min. Upon addition of 2 N HCl (70 mL, ca pH=3) to the reaction mixture, a precipitate was formed. Water (300 mL) was then added and the heterogeneous mixture was filtered under reduced pressure. The precipitate was rinsed further with water and dried in vacuo to give the desired product as an off-white solid (7.37 g, 58%): mp 209° C.; 1H NMR (300 MHz, DMSO-d6) δ 9.21 (d, J=2.5 Hz, 1H), 8.77 (dd, J=4.9, 1.7 Hz, 1H), 8.41 (dt, J=8.0, 1.7 Hz, 1H), 7.60 (dd, J=8.0, 4.9 Hz, 1H), 3.4 (br s, 1H); ESIMS m/z 276.2 (M+1).

المصدر