HCID 54465968, compound → (2S)-2-Amino-N,3,3-trimethylbutanamide

Participants

Reaction Steps

A solution of 100.0 g (406 mmol) of (S)-3,3,N-trimethyl-2-(1-phenylethylimino)-butyramide in 775 ml of methanol was hydrogenated in a 21 autoclave in the presence of 5 g of 5 percent Pd/C at 40° C. and at a pressure of 1 bar for 7 hours. Re-hydrogenation was carried out for 6 hours at 70° C. and under a pressure of 2 bar in order to complete the hydrogenolysis. After cooling the catalyst was filtered off and the filtrate was evaporated to dryness: 58.3 g (99.6%) of white crystals with 99.6% N-methyl-tert-leucinamide content, e.e. 97.2%. Recrystallization from 425 ml of cyclohexane yields (S)-N-methyl-tert-leucinamide as white crystals, m.p. 90°-93° C., [α]=-40.8 (c=1, CHCl3), 99.3% e.e. In order to determine the e.e value, the product was derivatized with (-)-camphanoyl chloride and the diastereomer mixture was analyzed by gas chromatography.

Provenance & Evidence