CONDENSATION DES NITRILES AVEC LES ORGANOZINCIQUES ALLYLIQUES. APPLICATIONS EN SERIE TERPENIQUE

Article abstract of DOI:10.1016/S0040-4020(01)91958-1

The reaction of 3-bromomethyl-2,5-dihydrothiophen-1,1-dioxide 6 and 2-bromomethyl-1,3-butadiene 7 with nitriles in the presence of the zinc-silver couple leads to a mixture of ketones 8,9, the pyrolysis of which give the ketones 10 and 11, corresponding respectively to acylation of isoprene at its methyl group from 8, and at C-3 from 9.The reaction of bromide 7 with nitriles leads also to the formation of ketones 10 which by acid isomerisation give the ketones 12 corresponding to an acylation at C-1 of isoprene.In the same way the reaction of 2-(1'-methyl-4'-cyclohexenyl)-3-bromo propene 13 with 3,3-dimethyl acrylonitrile give β- atlantone 14 which is isomerised in acidic medium to α-atlantone 15. 10,11-dihydro α and β-atlantone 16, 17 are obtained by the same procedure from 13 and 3-methyl butyronitrile.