Tributylstannylmethyl ether

Z)-Homoallylic alcohols. The tributylstannylmethyl ether of an allylic alcohol on treatment with n-butyllithium at —78° undergoes tin-lithium exchange followed by [2,3] sigmatropic rearrangement to a homoallylic alcohol. A valuable feature is that the (Z)-isomer is formed. An example is shown in equation (I). ... 

The first asymmetric total synthesis of (+)-astrophylline was accomplished in the laboratory of S. Blechert. The Still variant of the [2,3]-Wittig rearrangement was used to generate the 1,2-trans relationship between the substituents of the key cyclopentene intermediate. The tributylstannylmethyl ether substrate was transmetalated with n-BuLi, which initiated the desired [2,3]-sigmatropic shift to afford the expected homoallylic alcohol as a single enantiomer. 

Opening of epoxide 140 with tributylstannylmethyl magnesium is probably the best available route to stannane 136 [45] (Scheme 31). After protection of the C(2)-OH as a MOM ether, stannane 144 undergoes a facile cross-coupling reac-... 

Tin-lithium exchanges. A method for the preparation of a-hydroxy boronic esters takes advantage of the facile Sn/Li exchange of a-stannylalkyl MOM ethers. Subsequent reaction of the lithioalkyl ethers with boronic esters displaces one of the alkoxy groups of the latter." The reaction of chiral A-tributylstannylmethyl-2-methoxymethylpyrrolidine with BuLi and then aldehydes gives diastereomeric mixtures of P-amino alcohols. ... 

Danishefslqr and coworkers eirployed the [2,3]-Wtittig rearrangement in their synthesis studies toward the xenibellol core through tributylstannylmethyl allyl ether 20, prepared from 19. They subjected 20 to the rearrangement conditions with n-BuLi in THE at -78 °C to rt for 12 h... 

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