V. Popkova, M. Antipin, L. E. Vinogradova
Apr 1, 1992
Citations
0
Influential Citations
9
Citations
Journal
Heteroatom Chemistry
Abstract
Perfluoro-2-methyl-2-pentene-thiocyanate-3 reacts with ammonia to give 2,4-diaminoperfluoro-4-methyl-2-pentenethiocyanate-3 (4) and 2-aminoperfluoro-4, 4-dimethyl-4,5-dihydro-5-ethylidene-1,3-thiazole (5). Compound 4 is kinetically stable and at 150°C under-goes rotational isomerization to afford the cyclic isomer 2-amino-4,4-bis(trifluoromethyl)-4,5-dihydro-5-(1-aminoperfluoroethylidene) -1,3-thiazole (6). Intramolecular cyclizations, resulting in the thiazolines 5 and 6, proceed likewise via the Thorpe reaction. For compounds 4–6, X-ray diffraction analyses were undertaken and IR spectra in solution and in solid state were investigated. It is supposed that a high kinetic preference for formation of 4 and the fact that it does not undergo spontaneous cyclization in ammonolysis stem from the NH … N intramolecular hydrogen bonding between two amino groups.