solvent and ligand effects on the tandem addition-lithiation-electrophilic substitution of phenyllithium on α,β-unsaturated carbonyl compounds溶剂和配位效应的串联addition-lithiation-electrophilic替换phenyllithiumα,β-unsaturated羰基化合物.pdf

Int. J. Mol. Sci. 2005, 6, 97-103 International Journal of Molecular Sciences ISSN 1422-0067 © 2005 by MDPI /ijms/ Solvent and Ligand Effects on the Tandem Addition-Lithiation- Electrophilic Substitution of Phenyllithium on α,β-Unsaturated Carbonyl Compounds† N. Sbarbati Nudelman* and Alvaro Vázquez Department of Organic Chemistry, Facultad de Ciencias Exactas, Universidad de Buenos Aires. Pab. II, P. 3, Ciudad Universitaria, 1428 Buenos Aires, Argentina † Results presented in part at the XIV Symposium on Organic Chemistry (XIV SINAQO), Rosario (Argentina), Nov. 2003. * Author to whom correspondence should be addressed; Email: nudelman@qo.fcen.uba.ar Received: 2 June 2004; in revised form: 15 June 2004 / Accepted: 17 December 2004 / Published: 31 January 2005 Abstract: The reaction of phenyllithium with E-cinnamaldehyde is extremely sensitive to the reaction conditions and surprising changes in the product distribution were observed upon changes in the solvent, concentrations, duration or temperature of the reaction. For these reasons the above mentioned reaction was considered an appropriate model to examine solvent and aggregation effects of PhLi. On the other hand, when two or trhee equiv of phenyllithium are used, instead of one, the reaction transforms into a surprising tandem addition-lithiation-β-alkylation sequence, that can be successfully applied to the synthe