The ylide, generated with strong base, is a powerful methylene transfer reagent, converting aldehydes and ketones to epoxides; reaction with ɑ?-enones also gives epoxides (contrast Trimethyl-sulfoxonium iodide): J. Am. Chem. Soc., 87, 1353 (1965).Methylene transfer to allylic, propargylic, benzylic and primary alkyl halides and sulfonates results in formation of terminal alkenes in generally good yields: Tetrahedron Lett., 35, 5453 (1994). Reaction with Ag2O gives the corresponding hydroxide, which is a useful methylating agent for various functional groups, including carboxylic acids, phenols, thiols and N-heterocycles: J. Org. Chem., 44, 638 (1979). Both the iodide and the hydroxide have been used for the methylation of pyrimidine nucleosides; see, e.g.: J. Chem. Soc., Perkin 1, 13 (1989).