反应详情

5-tert-butyl 2-ethyl 6,7-dihydro[1,3]thiazolo[5,4-c]pyridine-2,5(4H)-dicarboxylate obtained in step V of example 1 was deprotected to get the hydrochloride salt of 4,5,6,7-Tetrahydro-thiazolo[5,4-c]pyridine-2-carboxylic acid ethyl ester. To a solution of a HCl salt of 4,5,6,7-Tetrahydro-thiazolo[5,4-c]pyridine-2-carboxylic acid ethyl ester (1 eq) in dichloromethane, triethyl amine (1.2 eq) was added at 0° C. and the reaction mixture was stirred for 15 min. To this, a solution of phenyl isothiocyanate (1 eq) in dichloromethane was added and the reaction was continued at room temperature for 3 h. Water was added and the organic layer was separated, dried over anhydrous Na2SO4 and concentrated under reduced pressure to afford crude product, which, on purification by column chromatography afforded—ethyl 5-(anilinocarbonothioyl)-4,5,6,7-tetrahydro[1,3]thiazolo[5,4-c]pyridine-2-carboxylate.

1. waitthe reaction was continued at room temperature for 3 h
2. customthe organic layer was separated
3. dry with materialdried over anhydrous Na2SO4
4. concentrationconcentrated under reduced pressure
5. customto afford crude product, which
6. customon purification by column chromatography