Dithioorthoformates having various alkoxy groups were obtained by copper(II) bromide-promoted oxidative coupling of bis(phenylthio)methyltributylstannane with alcohols. The dithioorthoformates thus prepared are useful precursors for alkoxymethylidene complexes of titanium, which transform carbonyl compounds into a variety of enol ethers. Even the alkoxymethylidene complexes having a terminal olefin moiety can be prepared and employed for carbonyl olefination without formation of ring-closing metathesis product.
carbene complexes - esters - ketones - olefination - titanium
