N-methyl-2-pyrrolidone → 5-Phenylthiophen-3-amine

Participants

Reaction Conditions

Reaction Steps

A mixture of methyl 3-amino-5-phenylthiophene-2-carboxylate (2.50 g, 10.7 mmol), 3.5 mL of N-methylpiperazine and 12 mL of N-methylpyrrolidinone is heated at 160° C. for 4 hours. The reaction mixture is cooled to room temperature and poured into 100 mL of water. The solids are collected by filtration washing with 50 mL of water. Ethyl acetate and hexane are added and the filtrate is decanted off from the gummy black residue. The filtrate is concentrated to provide 850 mg of 5-phenyl-3-thienylamine as a yellow solid, mp 76–78° C.; 1H NMR (DMSO-d6) δ 4.87 (s, 2H), 5.98 (d, J=1.5 Hz, 1H), 6.95 (d, J=1.5 Hz, 1H), 7.28 (m, 1H), 7.37 (t, J=7 Hz, 2H), 7.53 (d, J=7 Hz, 2H); MS 176.2 (M+H)+.

Provenance & Evidence