Thiourea → 871716-68-6

Participants

Reaction Steps

An ethanol (20 mL) solution of tert-butyl 2-(2-chloroacetyl)pyrrolidine-1-carboxylate (1.08 g, 4.4 mol) and thiourea (334 mg, 4.4 mmol) was stirred at 55 C for 70 hours. Upon completion of the condensation, the solution was evaporated. The solid was dissolved in CH2Cl2 (100 mL). It was washed with dilute NaHCO3 solution, dried and evaporated. Recrystallization from CH2Cl2/hexane afforded tert-butyl 2-(2-aminothiazol-4-yl)pyrrolidine-1-carboxylate. 1H NMR (400 MHz, CDCl3): mixture of rotamers: δ 8.81 (s, 2H, br), 6.22 and 6.15 (2s, 1H), 4.84 and 4.78 (2s, 1H), 3.62 and 3.44 (2m, 2H), 2.4-1.8 (m, 4H), 1.46 and 1.36 (2s, 9H). MS (ES+): M/Z 270 (M+H)+, 170 (M−C5H8O2)+.

Provenance & Evidence