Triethylamine → Methanesulfonic acid 4-(4-benzyloxycarbonylamino-3-fluoro-phenyl)-cyclohex-3-enyl ester

Participants

Reaction Steps

To a solution of [2-fluoro-4-(4-hydroxy-cyclohex-1-enyl)-phenyl]-carbamic acid benzyl ester (230 mg. 0.67 mmol) in DCM (5 mL) was added Et3N (0.2 mL, 1.7 mmol, 2 equiv.). The solution was cooled to an ice-water bath and then de-aerated by vacuum/nitrogen exchange. To this solution was transferred a solution of methanesulfonyl chloride (146 mg, 1.2 mmol, 1.5 equiv.) in DCM (2 mL). The clear solution was stirred in an ice-water bath for 1 h. TLC (50% EtOAc in heptane) indicated that the reaction was complete. The reaction was quenched by diluting with DCM (10 mL), followed by addition of NaHCO3 aq. (5 mL). The two layers were separated and the aqueous layer was extracted with DCM (2×5 mL). The combined extracts were washed with NaHCO3 aq. (5 mL), brine (5 mL), and dried (K2CO3). The solution was filtered through a silica gel pad, eluted with 5% MeOH in DCM to afford 248 mg (88%) of the title compound.

Provenance & Evidence