Titanocyclobutane Tebbe reaction

Carbene Chemistry. Isobutene reacts readily with car-benes and metallocarbenes to form substituted cyclopropanes (eqs 25-27). Reaction of Ethyl Diazoacetate with isobutene in the presence of a chiral copper catalyst affords the cyclopropane in high optical purity (eq 28). Isobutene has also been used to form titanocyclobutanes that are more stable forms of the Tebbe reagent (see L-Chlorobis(cyclopentadienyl)(dimethylaluminum)- L-methylenetitanium) (eq 29). ... 

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