Water → HCID 59382849, compound

Participants

Reaction Steps

To a solution of (S)-tert-butyl 1-(4-(tert-butyldimethylsilyloxy)cyclohexyl)-3-(methylamino)propan-2-ylcarbamate (57 g, 0.142 mol) and Et3N (28.8 g, 0.285 mol) in CH2Cl2 (600 mL) was added CbzCl (26.6 g, 0.156 mol) at −20° C., which was allowed to stir for 1 h at rt. The reaction mixture was treated with water (200 mL) and extracted with CH2Cl2 (3×100 mL). The organic layer was dried over Na2SO4 and evaporated. The residue was separated on a silica column to give the pure isomer (S)-tert-butyl 1-(4-(tert-butyldimethylsilyloxy)cyclohexyl)-3-(N-methyl-N-(benzyloxycarbonyl)amino)propan-2-ylcarbamate (5.5 g) and a fraction with a mixture isomers (33 g, total yield 51%). Mixture isomer: 1H NMR (CDCl3, 400 MHz) δ 0.02 (d, 6H), 0.88 (s, 9H), 1.16-1.29 (m, 5H), 1.41 (d, 9H), 1.60 (m, 51H), 1.83 (m, 1H), 2.95 (t, 3H), 3.00-3.40 (m, 1H), 3.49 (m, 1H), 3.89 (m, 2H), 5.11 (s, 2H), 7.34 (m, 5H).

Provenance & Evidence