Benzyl Alcohol → benzyl tert-butyl ((1S,3S)-cyclopentane-1,3-diyl)dicarbamate

Participants

Reaction Conditions

Reaction Steps

Diphenylphosphoryl azide (1.90 mL, 8.82 mmol) was added to a stirred mixture of (1S,3S)-3-[(tert-butoxycarbonyl)amino]cyclopentanecarboxylic acid (1.359 g, 5.93 mmol) and Et3N (1.65 mL, 11.84 mmol) in dry toluene (27.5 mL) and the resulting mixture was heated to 90° C. for 3 h. Benzyl alcohol (3.4 mL, 32.8 mmol) and DMAP (67 mg, 0.55 mmol) were added and the mixture was heated for an additional 16 h. The mixture was cooled and the solids were collected by filtration, rinsing with 1:1 toluene:hexane (4 mL), and dried to give the title compound as a white solid (1.649 g). The mother liquors were purified by silica gel chromatography (5% CH2Cl2, 10-80% EtOAc/hexane gradient), to give additional product (0.386 g). The combined solids are 88 area % pure at 215 nm; MS=235.3 (M+1-isobutylene and CO2).

Provenance & Evidence