Triethylamine → Tert-butyl 4-[(3-chlorophenyl)(1-hydroxycyclohexyl)acetyl]piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of (3-chlorophenyl)(1-hydroxycyclohexyl)acetic acid (Reference Example 1-a) (5.4 g, 20.1 mmol), benzotriazol-1-yloxytris(dimethylamino)phosphonium hexafluorophosphate (14.22 g, 32.15 mmol), and tert-butyl 1-piperazinecarboxylate (5.99 g, 32.15 mmol) in methylene chloride (20 mL) was treated with triethylamine (8.4 mL, 60.3 mmol). The reaction was stirred at 25° C. for 16 h, after which time the solvent was removed in vacuo and the product was purified via Biotage Horizon (FLASH 40 M, silica, gradient from 0% EtOAc/hexane to 30% EtOAc/hexane) to yield 7.10 g (81%) tert-butyl 4-[(3-chlorophenyl)(1-hydroxycyclohexyl)acetyl]piperazine-1-carboxylate as a white foam. HRMS: calcd for C23H33ClN2O4, 436.2129; found (ESI_FT), 437.21996.

Provenance & Evidence