Metallation of Hetero-Substituted Unsaturated Systems

Abstract

This chapter deals with the generation of polar organometallic intermediates of the type

,

and

in which X represents a group containing a heteroatom directly linked to the double-bond system. Practically all these polar metal derivatives are generated by direct metallation of the corresponding unsaturated systems

,

and

or the isomeric systems

and

. The intermediates in which X is halogen (mostly chlorine) are stable only at very low temperatures [80].