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) is 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 is removed in vacuo to give an oil, which is then dissolved in EtOAc. After washing with H2O, the organic phase is back-extracted with EtOAc and the organic layers are combined and washed sequentially with additional H2O, saturated NaHCO3 and saturated NaCl. The organic phase is dried, concentrated and the resulting crude product is 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