Water → HCID 19100767, compound

Participants

Reaction Steps

Di-t butyl-4-phenylthiophene-2,3-dicarbamate (0.9 g crude oil from the preceding step) was dissolved in a mixture of 7 ml of acetic acid and 7 ml of diethyl oxalate and heated to reflux for three hours. While still hot, 7 ml of water was added, and the mixture stirred overnight at room temperature to precipitate 0.27 g of crude title compound. Three crystallisations from acetic acid combined with charcoal (Norit SU 18) and one from ethanol/acetic acid (1:1) produced 65 mg of pure title compound, m.p.>300° C. 1H-NMR (DMSO-D6, δ): 7.1 (s, 1H), 7.4 (m, 5H), 11.5 (br.s, 1H), 12.5 (br.s, 1H). MS: 244.

Provenance & Evidence