Methanol → Tert-butyl 2-(cyclopentylamino)acetate

Participants

Reaction Steps

Sodium cyanoborohydride(1.9 g) was added portionwise to a stirred mixture of cyclopentanone(2.1 g), glycine tert-butyl ester hydrochloride(5.0 g), water(12 ml) and methanol(25 ml) during 15 min at water-bath temperature. The resulting mixture was stirred for 4 hr, diluted with 20% H3PO4 (40 ml) and water(20 ml), and extracted with ether(80 ml). The aqueous layer was made alkaline(pH 10) with 20% NaOH and extracted with CHCl3 (50 ml). The extract was dried(Na2SO4) and concentrated in vacuo to give an oily residue, which was purified by silica gel column chromatography(ethyl acetate:hexane=3:1) to yield N-cyclopentylglycine tert-butyl ester(4.5 g) as a pale yellow oil.

Provenance & Evidence