Allyltin trihalide

Alkoxy-substituted allylstannanes are transmetalated on treatment with Sn(IV) halides to give allyltin trihalides which react with aldehydes with effective remote asymmetric induction [62]. For example, the 5-benzyloxy-4-methylpent-2-enylstan-nane gives predominantly the 1,5-anti products with useful stereoselectivity (Eq. 37) [62b]. Allylstannanes and 5-benzyloxy-4-methylpent-2-enylsilanes also react with aldehydes with modest levels of 1,5-induction after treatment with SnCU. Trans-metallation to give intermediate allyltin trihalides might be involved (Eq. 38) [63]. 

Halogen (Cl/Br) exchange in allyltin trihalides studied by 2D EXSY. 

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