反应详情

To a stirred solution of trans 1-[2-(5-Chloro-thiophen-2-yl)cyclopropyl]-ethanone O-methyl-oxime (1.2 g; 5.2 mmol) prepared as described in example P25, in acetic acid (15 ml) at ambient temperature was added portionwise sodium cyanoborohydride (1.0 g; 15.7 mmol). The reaction mixture was stirred for 16 hours at ambient temperature then poured on sodium hydroxide solution (0.5M; 150 ml) and extracted with dichloromethane (3×50 ml). Combined organic layers were dried over anhydrous sodium sulphate. The solvent was removed in vacuo and the residue was purified by flash chromatography over silica gel (elution gradient: cyclohexane/ethyl acetate 99:1 to 50:50) to afford 0.91 g (79% of theory) of trans N-{1-[2-(5-chloro-thiophen-2-yl)-cyclopropyl]-ethyl}-O-methyl-hydroxylamine as a mixture of diastereomeres in form of a clear viscous oil.

1. additionthen poured on sodium hydroxide solution (0.5M; 150 ml)
2. extractionextracted with dichloromethane (3×50 ml)
3. dry with materialCombined organic layers were dried over anhydrous sodium sulphate
4. customThe solvent was removed in vacuo
5. customthe residue was purified by flash chromatography over silica gel (elution gradient: cyclohexane/ethyl acetate 99:1 to 50:50)