Ethanol → (2,5-Diphenyl-pyrrol-1-yl)-carbamic acid tert-butyl ester

Participants

Reaction Steps

A solution of dibenzoylethane (5 g, 21.0 mmol) and t-butyl carbazate (3.98 g, 30.1 mmol) in EtOH (170 mL) and AcOH (21 mL) was heated to reflux under Ar for 4.5 h, cooled to rt and diluted with water (400 mL). The resulting suspension was stirred under Ar at rt for 3 h, and then allowed to settle overnight at rt. The solid was filtered, washed with small portions of water and dried in vacuo to afford (2,5-Diphenyl-pyrrol-1-yl)-carbamic acid tert-butyl ester (6.72 g, 96%) as a white solid: 1H NMR (CDCl3, chemical shifts in ppm relative to TMS): 1.14 (s, 3H), 1.38 (s, 6H), 6.35 (s, 2H), 6.84 (bs, 2H), 7.29-7.53 (m, 10H).

Provenance & Evidence