Water → HCID 13245578, compound

Participants

Reaction Steps

43.3 g (0.10 mole) of the 1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl)pyridine-3,5-dicarboxylic acid 3-methyl ester 5-(6-hydroxyhexyl) ester produced in Step i described above was dissolved along with 29.5 g (0.16 mole) of tosyl chloride in 200 ml of chloroform, to which was added dropwise 25.0 g (0.32 mole) of pyridine with stirring under ice cooling. This reaction mixture was allowed to stand at room temperature for 2 hours, then, after adding 100 ml of water, was stirred for 3 hours. The chloroform layer of the obtained liquid was separated, washed with 200 ml of 0.02 N sulfuric acid, 200 ml of water and 200 ml of saturated aqueous sodium bicarbonate successively, and dried over anhydrous sodium sulfate. This chloroform solution was chromatographed on a silica gel column using a mixed solution of benzene-ethyl acetate (the ratio by volume of 8:1) as an eluent to obtain 36.6 g (yield 62.5%) of the 1,4-dihydro- 2,6-dimethyl-4-(3-nitrophenyl)pyridine-3,5-dicarboxylic acid 3-methyl ester 5-(6-tosyloxyhexyl) ester as a pale yellow oil.

Provenance & Evidence