Kauffmann olefination

The reagent was generated in situ by conversion of different halogenides of molybdenum or tungsten with methyllithium at low temperatures (−78 °C). During the warm-up process the formation of the active reagent occurs. NMR-experiments have shown that the active reagent is not a Schrock carbene (e.g. Tebbe-reagent). == Mechanism ==

Mechanism experiments shows that the olefination process is a sequence of cycloaddition and cycloelimination steps. == Applications ==

For a long time this reaction had no applications in synthetic organic chemistry. In 2002 it was used in a total synthesis of the terpene gleenol as a mild and non-basic reagent in a one-pot-protocol with an olefin metathesis step with Grubbs catalyst. It is remarkable that the organometallic catalyst tolerates the inorganic reaction products. == References ==