Stoichiometric reaction of titanacyclopentadiene compounds with allylic ethers: Regiochemistry of methylenecyclohex-3-ene formation

Article abstract of DOI:10.1016/0040-4020(94)01133-K

The titanacyclopentadiene complexes [(ArO)₂Ti(C₄Et₄)] (1a), [(ArO)₂Ti(C₄Et₂(CH₂)₄)] (1b) and [(ArO)₂Ti(C₄Bu₂(t)H₂)] (1c) (ArO = 2,6-diphenylphenoxide) react with allylphenylether to produce new organometallic products containing cyclohexadienemethyl and phenoxide ligands. Hydrolysis of these compounds leads to the formation of single regioisomers of substituted methylenecyclohex-3-ene along with two equivalents of 2,6-diphenylphenol and one equivalent of phenol. A reaction sequence involving initial (2+2+2) cycloaddition followed by cleavage of a phenyl ether bond is discussed.