Dimethyltitanocene is known as Petasis reagent. It is prepared from titanocene dichloride and methyllithium or methylmagnenesium bromide. A variety of carbonyl compounds react with Petasis reagent in THF or Toluene at 60-75 deg C to produce terminal alkenes. Petasis reagent converts sulfoxide, selenoxide and pyridine N-oxide to sulfide, selane and 2-methylpyridine respectively. Enol esters react with excess Petasis reagent under heating condition to produce cyclic enol ethers.
