L. Klemm, Jun Wang, L. Hawkins
May 1, 1995
Citations
1
Influential Citations
5
Citations
Journal
Journal of Heterocyclic Chemistry
Abstract
3-Amino-2-carbamoylthiophene (2) was obtained in 75% yield by reaction of methyl 3-aminothiophene-2-carboxylate with saturated aqueous ammonia containing ammonium chloride catalyst at room temperature over a period of 2,3 months, Treatment of 2 with cyclopentanone, cyclohexanone, and cycloheptanone in ethanol at pH 3.4 gave facile formation of 2-carbamoyl-3-cycloalkylidenaminothiophenes in yields of 73%, 86%, and 60%, respectively. Infrared and 1H nmr spectra of these imines indicate that they occur in intramolecularly hydrogenbonded form, i.e. with chelate rings. Comparison is made with reported syntheses and reactions of 2 and its isosteric 2-aminobenzamide.