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The ylide, generated with strong base, is a powerful methylene transfer reagent, converting aldehydes and ketones to epoxides; reaction with ɑß-enones also gives epoxides (contrast Trimethylsulfoxonium iodide, A14589): J. Am. Chem. Soc., 87, 1353 (1965):/n
Other conditions for addition to aldehydes include: phase-transfer catalysis: Angew. Chem. Int. Ed., 12, 845 (1973), KOH in acetonitrile: Tetrahedron Lett., 23, 5283 (1982), or KF on alumina: Tetrahedron, 41, 1259 (1985). With aryl aldehydes, the use of KO-t-Bu gives improved results by suppressing the competing Cannizzaro reaction: Org. Prep. Proced. Int., 27, 219 (1995). A simplified, solvent-free method employing KO-t-Bu has been reported for ketones: Heterocycles, 46, 185 (1997). With excess of the sulfonium ylide, ketones or epoxides give good yields of allylic alcohols, whereas aldehydes give poor yields. Under similar conditions, the sulfoxonium ylide gives oxetanes: Tetrahedron Lett., 35, 2009, 5449 (1994)./n
Methylene transfer to imines and arylhydrazones gives aziridines and N-arylaminoaziridines respectively: Synthesis, 330 (1983)./n
Addition to vinyl sulfones gives cyclopropyl sulfones: J. Org. Chem., 29, 3277 (1964). Similarly, vinylsulfonates and sulfonamides give cyclopropanes in fair to good yields: J. Org. Chem., 33, 3849 (1968)./n
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)./n
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)./n
Dichiarazioni di rischio (UE): H315-H319-H335
Causes skin irritation. Causes serious eye irritation. May cause respiratory irritation.
Dichiarazioni precauzionali: P261-P280a-P305+P351+P338-P304+P340-P405-P501a
Avoid breathing dust/fume/gas/mist/vapours/spray. Wear protective gloves and eye/face protection. IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. IF INHALED: Remove to fresh air and keep at rest in a position comfortable for breathing. Store locked up. Dispose of contents/container in accordance with local/regional/national/international regulations.