benzyl (5S)-N,N-bis(tert-butoxycarbonyl)-5-(2,3-difluorophenyl)-6-nitro-D-norleucinate → (5S)-N2,N2-Bis(tert-butoxycarbonyl)-5-(2,3-difluorophenyl)-D-lysine

Participants

Reaction Steps

A mixture of benzyl (5S)—N2,N2-bis(tert-butoxycarbonyl)-5-(2,3-difluorophenyl)-6-nitro-D-norleucinate from Step C (15.5 g, 26.8 mmol) and 10% Pd/C (12.0 g) in EtOH (175 mL), was hydrogenated at 55 psi for 18 h. An additional portion of 10% Pd/C (4.0 g) was added and the reaction mixture was hydrogenated at 55 psi for a further 18 h. The reaction mixture was filtered through Celite, washing with EtOH, and the filtrate was concentrated in vacuo to afford the title compound. MS: m/z=459 (M+1).

Provenance & Evidence