Contribution to the study of some palladium-complex-catalyzed carbon-carbon bond-forming reactions

Abstract

Significant contributions have been developed for the knowledge of the following r-allylpalladium catalyzed reactions: -"one pot" modification of the wittig reaction. -nucleophylic allylation. -with reference to the first-one, we have demonstrated the reaction doesn't work if the allylic alcohol hasn't, at least, a nonsubstituted end or if the clouble bond belongs to an aromatic system. Morcover, if the double bond is conjugated, complex isomeric mixtures of condensation products and, mainly, cyclic derivatives of them are obtained. We explain this fact as a result of ns-palladium complexes intermediary. -we have extended the scope of the second reaction to cyclic b-dicarbonylic compounds, for which we have developed an efficient c-allylation method using primary and secondary allylic acetates and carbonates as reactives. -for the triacetic acid lactone allylic derivatives, regioselective hydrogenation of the exocydic double bond extends the scope of the synthesis of saturated derivatives. -some simple mechanistic studies permormed with this nucleophile have demonstrated the reaction to occur: -under thermodynamic control: o-alkylation is reversible under these conditions. -with configuration retention at the reactive center, probably through double inversion. -on the end bearing the more electron-donating substituent, if the steric hindrance is similar. This es also true for the acetylacetone.