Scope
The Tebbe reagent is used in organic synthesis for carbonyl methylenation. This conversion can also be effected using the Wittig reaction, although the Tebbe reagent is more efficient especially for sterically encumbered carbonyls. Furthermore, the Tebbe reagent is less basic than the Wittig reagent and does not give the β-elimination products.
Methylenation reactions also occur for aldehydes as well as esters, lactones and amides. The Tebbe reagent converts esters and lactones to enol ethers and amides to enamines. In compounds containing both ketone and ester groups, the ketone selectively reacts in the presence of one equivalent of the Tebbe reagent.
The Tebbe reagent methylenates carbonyls without racemizing a chiral α carbon. For this reason, the Tebbe reagent has found applications in reactions of sugars where maintenance of stereochemistry can be critical.
The Tebbe reagent reacts with acid chlorides to form titanium enolates by replacing Cl-.
Read more about this topic: Tebbe's Reagent
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