反应详情

A solution of 194 g of 6-(Chloro-difluoro-methyl)-2-(3-methoxy-propyl)-nicotinic acid methyl ester (prepared according to WO 04/078729) in methanol (ca. 2 liter) and triethylamine (100 ml) is hydrogenated at 1 Atm hydrogen pressure in the presence of 2 g of 5% palladium supported on carbon. After completion of the reduction the reaction mixture is filtered through hyflo, and the filtrate diluted with water and the water/methanol mixture then extracted with ethyl acetate. The combined ethyl acetate extracts are washed with saturated aqueous sodium chloride solution, dried over magnesium sulphate and then concentrated in vacuo to give 194.2 g 6-Difluoromethyl-2-(3-methoxy-propyl)-nicotinic acid methyl ester as a pale coloured oil.

1. filtrationAfter completion of the reduction the reaction mixture is filtered through hyflo
2. additionthe filtrate diluted with water
3. extractionthe water/methanol mixture then extracted with ethyl acetate
4. washThe combined ethyl acetate extracts are washed with saturated aqueous sodium chloride solution
5. dry with materialdried over magnesium sulphate
6. concentrationconcentrated in vacuo