IMINE CHEMISTRY-II.A NEW ROUTE TO CYCLIC ENAMINONES FROM IMINES AND β-PROPIOLACTONE OR α,β-UNSATURATED ACIDS. THE PREPARATION OF ENAMINO-THIONES

Article abstract of DOI:10.1016/0040-4020(80)88031-8

Imines, formed from cyclohexanone and primary aromatic and aliphatic amines, were reacted with β-propiolactone, acrylic, crotonic, and methacrylic acids to give as main products bicyclic lactams, 3,4,5,6,7,8-hexahydro-2-quinolinone, 2, and enaminones, 2,3,5,6,7,8-hexahydro-4-quinolinone, 3.The enaminones 3 and a series of noncyclic enaminones 11 were reacted with 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide, 9, a new thiation reagent, giving the corresponding enamino-thiones 10 and 12, respectively.Compound 2a was also reacted with 9 giving N-phenyl- 3,4,5,6,7,8-hexahydro-2-quinolinthione, 13a. 360 MHz (1)H NMR and 90.25 MHz (13)C NMR data are reported for the compounds 2a, 3a and 10a.