Stannanes reaction with organolithium compounds

Non-aromatic organolithium compounds can be prepared by transmetallation of resin-bound stannanes [25] or by deprotonation of alkynes [26], triphenylmethane [27], or other resin-bound C II acidic compounds with lithium amides or similar bases (Figure 4.3). The reaction of polystyrene-bound trialkylboranes with diethylzinc yields resin-bound alkylzinc derivatives [28]. 

Alkenyllithium compounds can also be prepared by metallation of alkenes, particularly when alkenyl hydrogens are rendered acidic by an a-substituent (equation 22). Transmetallation of alkenyl stannanes with organolithium reagents gives alkenyllithium compounds with retention of alkene stereochemistry (equation 23). Tin-lithium transmetallation has been used to prepare 1,4-dilithio-l,3-butadiene. Monosubstituted alkenyllithium compounds RHC=CHLi, can also be prepared from the corresponding diorganotel-luride, RHC=CHTeBu, by reaction with butyllithium in... 

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