1-Ethyl-3-(3'-dimethylaminopropyl)carbodiimide → tert-butyl (NE)-N-[[(8-bromo-4,5-dihydrothieno[3,2-d][1]benzoxepine-2-carbonyl)amino]-methylsulfanylmethylidene]carbamate

Participants

Reaction Steps

A mixture 8-bromo-4,5-dihydrobenzo[b]thieno[2,3-d]oxepine-2-carboxylic acid (10.0 g, 30.3 mmol), EDCI (7.5 g, 36.4 mmol) in DCM (200 mL) was stirred at room temperature for 10 min, then DMAP (7.39 g, 60.6 mmol) was added by one portion. 10 minutes later, N-Boc-2-Methyl-isothiourea (6.9 g, 36.4 mmol) was added. The reaction mixture was stirred at room temperature overnight. After removal of the solvent, the residue was treated with methanol/water (20 mL, 1:1) to afford 10.2 g of methyl N′-8-bromo-4,5-dihydrobenzo[b]thieno[2,3-d]oxepine-2-carbonyl-N-Boc-carbamimidothioate. Yield: 67%. 1H NMR (CDCl3, 400 MHz): δ12.33 (s, 1H), 7.95-7.51 (m, 2H), 7.35-6.94 (m, 2H), 4.28-4.25 (m, 2H), 3.15-3.30 (m, 2H), 2.52 (s, 3H), 1.51-1.45 (s, 9H). LC-MS: m/z=497 [M+H+]

Provenance & Evidence