tert-Butanol → HCID 11630600, compound

Participants

Reaction Steps

A solution of 3-cyano-1-ethyl-1H-indole-6-carboxylic acid (0.60 g, 2.80 mmol) from Example 1E, step A, in t-butanol (20 mL) was treated with Et3N (0.46 mL, 3.36 mmol) and diphenylphosphoryl azide (0.73 mL, 3.36 mmol) and then heated at reflux for 4 h. After cooling to room temperature, most of the t-butanol was removed in vacuo to give an oil, which was then dissolved in EtOAc. After washing with H2O, the organic phase was back-extracted with EtOAc and the organic layers were combined and washed sequentially with additional H2O, saturated NaHCO3 and saturated NaCl. The organic phase was dried, concentrated and the resulting crude product was purified by chromatography over silica gel using EtOAc/CH2Cl2 (0-1%) to afford 0.52 g (65%) of t-butyl (3-cyano-1-ethyl-1H-indol-6-yl)-carbamate as a white solid.

Provenance & Evidence