PYRROLES FROM KETOXIMES AND ACETYLENE. 24. ACIDIC HYDROLYSIS OF 1-VINYLPYRROLES

Article abstract of DOI:10.1007/BF00506611

The hydrolysis of 2-methyl-, 2-phenyl-, and 3-methyl-2-phenyl-1-vinylpyrroles and 1-vinyl-4,5,6,7-tetrahydroindole in the presence of HCl, H2SO4, NH2OH*HCl, acetic acid, and H2O2 in aqueous, aqueous dioxane, and aqueous alcohol solutions leads to oligomers with complex structures and compositions, viz., products of acidic catalytic and oxidative condensation of the starting compounds and the resulting pyrroles both with one another and with the liberated acetaldehyde. 2-Phenylpyrrole was obtained in 52percent yield from 1-vinyl-2-phenylpyrrole by hydrolysis in a dilute (0.5percent) solution with excess NH2OH*HCl, which ties up the acetaldehyde.