Carbon Dioxide → 5-tert-Butoxycarbonylamino-2-chloroisonicotinic acid

Participants

Reaction Conditions

Reaction Steps

A stirred solution of (6-chloro-pyridin-3-yl)-carbamic acid tert-butyl ester (3.28 g, 14.3 mmol) and TMEDA (6.7 mL, 44.4 mmol) in Et2O (100 mL) at −78° C. was treated with n-BuLi (4.3 mL, 10 M, 43 mmol). After stirring the mixture at −78° C. for 2 hours CO2 was bubbled into the reaction and the solution was warmed to 0° C. Water was added and the mixture was extracted with EtOAc. The aqueous layer was acidified and extracted with Et2O. The Et2O layer was washed with brine, dried (MgSO4) and the solvent was removed in vacuo. The residual solid was triturated with Hexane/Et2O to give 25A (1.38 g, 35%) HPLC Rt=2.98 min.

Provenance & Evidence