The Reaction of Stannylmetallic Compounds with Organic Electrophiles

The reaction of a stannylmetallic compound with an organic halide or other organic electrophile (e.g. equation 4-26) is a versatile process. 

Commonly, the metal M is lithium, when the reagents have been described as stannylanionoids. These reagents can readily be prepared from the tin halides and metallic lithium (equation 4-27), or the distannanes and an alkyllithium (equation 4-28), or the tin hydrides and LDA (equation 4-29) (see Section 19.1.1). 

Some typical reactions of stannylanionoids which result in the formation of a C-Sn bond are shown in Table 4-1. Primary and secondary alkyl halides react mainly by substitution, but tertiary alkyl halides give mainly elimination. Aryl halides can also give arynes through elimination reactions. 

The rates of the reactions, however, depend on the structure of the stannyl anion and of the organic substrate, on the nature of the solvent, and on the presence or absence of radical initiators, particularly light. Four principal mechanisms have been identified. 

These reactions involve inversion at the reaction centre, for example  

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