Coupling reactions of vinylketene silyl acetals promoted by titanium tetrachloride
作者:Kenji Hirai、Iwao Ojima
DOI:10.1016/s0040-4039(00)81527-0
日期:1983.1
Homo- and cross-couplings of vinylketene silyl acetals were found to be effectively promoted by titaniumtetrachloride to give the corresponding unsaturated diesters in good yields. The reactionsbetween two different ketene silyl acetate afforded the corresponding cross-coupling products in unexpectedly good selectivities.
The photochemicalringexpansion of dispirosubstitutedcyclobutane-1,3-diones in methanol has been investigated. The formation of ringexpansion product was strongly dependent on the spiro ring size of dispiro substituent. The ring expanded acetal was obtained in a low yield when the spiro ring of dispirosubstitutedcyclobutane-1,3-diones was a five- or seven-membered ring. This is the first example