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Please login to access the full content or check if you have access via Variation 1: With Tebbe's Reagent

DOI: 10.1055/sos-SD-032-00627

Milata, V.; Rádl, S.; Voltrová, S.Science of Synthesis, (200832661.

Tebbe's reagent, μ-chloro-μ-methylenebis[2(η5)-cyclopentadienyl](dimethyl-1κ2C-aluminum)titanium (214), which is commercially available as a solution in toluene, can be prepared from dichlorobis(η5-cyclopentadienyl)titanium(IV) and trimethylaluminum in toluene.[‌193‌] Although it reacts readily with ketones and amides, its reactivity with esters is low. However, a highly reactive bis(η5-cyclopentadienyl)(methylene)titanium(IV) (215) is generated by the addition of a Lewis base, such as pyridine or tetrahydrofuran, and the resulting reagent can be used for the methylenation of a wide range of esters to form the corresponding vinyl ethers under very mild conditions (Scheme 99).

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