Carbonyl compounds trimethylsilyldiazomethane

Miscellaneous Reactions. Trimethylsilyldiazomethane converts acid- and base-sensitive maleic anhydride derivatives into the corresponding bis(methyl esters) (eq 70). Terminal silyl enol ethers are conveniently prepared from aldehydes by first treating the carbonyl compound with TMSC(Li)N2, followed sequentially by methanol and Rh2(OAc)4 (eq 71). The method works well with base-sensitive substrates and is superior to the attempted regioselective deprotonation/O-silylation of the corresponding methyl ketone. ... 

From Epoxysilanes.—Epoxysilane rearrangements continue to provide useful routes to carbonyl compounds. For instance, homologation of a ketone to the corresponding aldehyde using lithium trimethylsilyldiazomethane (2) involves the intermediate formation and the subsequent hydrolysis of an a,/3-epoxysilane (3). Furthermore, it has been shown that pyrolysis of a,/8-epoxysilanes yields silyl enol ethers which, on hydrolysis, would give carbonyl compounds structurally isomeric to those which would be obtained by direct hydrolysis (Scheme 7). ... 

As far as we can tell, there is only one intermolecular type cd approach to 3-pyrroUn-2-ones that has appeared in the hterature. Aoyama and Shiori investigated the use of hthium trimethylsilyldiazomethane 347 to generate alkylidenecarbenes from carbonyl compounds alkylidene carbenes are useful intermediates that can be used to form new rings including 3-pyrrolin-... 

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