Sulfuric Acid → Tert-butyl octahydro-1H-indole-2-carboxylate

Participants

Reaction Steps

Octahydro-indole-2-carboxylic acid 11b (5.0 g, 29.5 mmol, purchased from Bachem) was suspended in 200 mL of CHCl3 then cooled in a dry ice/acetone bath. H2SO4 (120 uL/mmol) was added followed by bubbling in excess isobutylene. The mixture was sealed and the ice bath removed. The mixture was stirred at RT for 12 hours. The reaction mixture was carefully unsealed after cooling and concentrated. EtOAc was added and washed with saturated sodium bicarbonate soln, brine, dried over sodium sulfate, then filtered and concentrated to give octahydro-indole-2-carboxylic acid tert-butyl ester 12b (6.65 g, 29.5 mmol, 100%).

Provenance & Evidence