Tebbe methylenation organometallic reagents

There are other organometallic derivatives that give Wittig-type olefination reactions, with titanium derivatives being the most commonly used. The initial addition reaction to the carbonyl gives a transient metal-ated alcohol that leads to an alkene. An example is the Tebbe reagent, which exists as a bridged methylene species (see 683), where Cp is cyclopentadienyl. 9 The aluminum species can be varied to include chloride... 

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