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 solution of benzyl (5S)—N,N-bis(tert-butoxycarbonyl)-5-(2,3-difluorophenyl)-6-nitro-D-norleucinate (15.5 g, 26.8 mmol) and 10% Pd/C (12.0 g) in EtOH (175 mL, SureSeal from Aldrich), was hydrogenated at 55 psi overnight. After 18 h, another 4 g of 10% Pd/C was added and the reaction hydrogenated at 55 psi for another 18 h. The reaction was filtered through Celite with more EtOH and concentrated to afford the title compound (12.0 g). MS 459.2 (M+1).

Provenance & Evidence