Water → 1-tert-butyl 2-methyl (2S,4R)-4-[(8-bromophenanthridin-6-yl)oxy]pyrrolidine-1,2-dicarboxylate

Participants

Reaction Conditions

Reaction Steps

To a solution of the product mixture from Step 2 (176 mg, 0.642 mmol) in NMP (1.5 mL) was added 1-tert-butyl 2-methyl (2S,4S)-4-{[(4-bromophenyl)sulfonyl]oxy}pyrrolidine-1,2-dicarboxylate (373 mg, 0.803 mmol) and Cs2CO3 (418 mg, 1.29 mmol). The mixture was then heated to 60° C. for 18 h, and worked up with water and EtOAc. The organic layer was washed with brine, dried over MgSO4, and the solvent was removed in vacuo. The crude material was purified on silica (gradient elution, 10-50% EtOAc/hex) to yield the title compound as a 1:1 mixture with the expected regioisomer. LRMS ((M-Boc)+H)+=401.2.

Provenance & Evidence