Stannylmethyl ether

From a stannylmethyl ether electrolysis, MeOH, 90% yield. ... 

There are other means of generating the anions of allyl ethers. One of the most useful for synthetic purposes involves a lithium-tin exchange on stannylmethyl ethers (see Section 7.1.2.4).295... 

Rearrangements of acyclic stannylmethyl ethers such as 168 may follow the stereospecificity evident with their cyclic counterparts.95... 

We employed tributyl(phenoxymethyl)stannane 73a instead of silylmethyl ethers, expecting that the alkoxymethylation would proceed more efficiently. When a methanol solution of 73a and 2-cyclohexen-l-one 14d was irradiated in the presence of DCN as a photosensitizer through a UV cut filter h > 320 nm), 3-(phenoxymethyl)cyclohexan-l-one 74a was obtained in 65% yield. By the use of stannylmethyl ethers having electron-rich aryl groups, the aryloxymethylation was facilitated. In particular, the ary-loxymethylation product 74b was obtained in 80% yield with 3,4-methylenedioxyphenoxy derivative 71b (Scheme 30). ... 

Z)-Trisubstitutedalkenes. Still and Mitra have described an efficient synthesis of alkenes of this type from allylic alcohols by a [2.3] sigmatropic Wittig rearrangement. The alcohol 2 is converted into the allyl stannylmethyl ether (3), which can be isolated if desired. Treatment with n-butyllithium results in tin-lithium exchange and rearrangement to the homoallylic alcohol 4 in 95% overall yield. When 3 is transmetalated and immediately quenched with cyclohexanone, 5 is obtained in 73% yield. 

The deoxychlorosucrose O-methyl ether derivatives (2) - (5) have been synthesized from appropriate partially protected precursors. Some partially methylated cyclomalto-hexaose and -octaose compounds are mentioned in Chapter 4. Complete H-and C- n.m.r. assignments have been made for a number of O-methyl derivatives of a- and -D-galactopyranose. 3-0-Stannylmethyl ethers (6) have been reported. ... 

Intermediate 40 would be produced through a coupling reaction between the appropriately functionalized decalin aldehyde 41 (available from alcohol 42) and 3-lithio-y-pyrone 23. Intermediate 42 would be formed through the strategic [2,3]-Wittig rearrangement of stannylmethyl ether 43. On the basis of the results accumulated from the nalanthalide synthesis (cf. Section Total Synthesis of (—)-Nalanthalide and Scheme 6), we expected that the C9 stereogenic center and the C8 exo-methylene function in the product 42 would be simultaneously formed. Intermediate 43, in turn, would be derived from 14 [17]. 

The exocyclic stannylmethyl allylic ethers 173abc gave the [2,3]-products 178 in 60%, 69%, and 64% yields, respectively fScheme 17.251. 

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