反应详情

A solution of N-(carbobenzyloxyaminosulfonyl)-DL-valine methyl ester (28.5 g) in methanol (200 ml) under nitrogen was cooled to 0° C. and 1.8 g of 10% Pd/C was added. The mixture was placed into a Parr Apparatus and hydrogenated for 2 hours. The catalyst was removed on a pad of CELITE® and the filtrate was concentrated in vacuo and purified by flash silica gel chromatography (ethyl acetate/hexane, 1:1) to afford 17.2 g (96%) of N-(aminosulfonyl)-DL-valine methyl ester (Formula VII: R=CH3 ; R1 =H; R2 =isopropyl; R3 =H) as a solid.

1. customThe catalyst was removed on a pad of CELITE®
2. concentrationthe filtrate was concentrated in vacuo
3. custompurified by flash silica gel chromatography (ethyl acetate/hexane, 1:1)