Crotyltin compounds

Martin used a tin-coupling reaction in a synthesis of erythronolide A.302 Keto-aldehyde 463 reacted with the crotyltin compound shown, in the presence of BF3 to give a 66% yield of the syn-diastereomer (464), along with 16% of the anti-diastereomer. 

Unfortunately, substitution in the y-position, such as in crotyltin, led to poorly reactive allyltins, due to the decrease in the addition rate of the radicals to the double bond. It has been established that, generally, the competitive allylic hydrogen abstraction became predominant, destroying the crotyltin reagent548. The use of y-substituted allyltins for the photo-induced radical allylation of carbonyl compounds represents an interesting... 

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