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Trimethylsulfoxonium iodide reacts with sodium hydride to prepare dimethyloxosulfonium methylide, which is used as a methylene-transfer reagent in synthetic chemistry. It is used to prepare ylide, which reacts with carbonyl compounds to get epoxides. Further, it reacts with alfa,beta-unsaturated esters to get cyclopropyl esters.
The ylide, generated with strong base, is a methylene transfer reagent.
For an example (conversion of cyclohexanone to the epoxide), see: Org. Synth. Coll., 5, 755 (1973). In contrast to Trimethylsulfonium iodide, A12639, reaction with ɑß-unsaturated ketones occurs by 1,4-addition to give cyclopropanes: J. Am. Chem. Soc., 87, 1353 (1965):
Efficient addition to enones has been effected with a highly basic system consisting of KOH in DMSO with a phase-transfer catalyst: Synth. Commun., 26, 1785 (1996).
Reaction with epoxides gives oxetanes, unlike the sulfonium ylide which gives allylic alcohols: J. Org. Chem., 48, 5133 (1983); Synthesis, 1140 (1987); cf Tetrahedron Lett., 35, 5449 (1994):
Similarly, N-arenesulfonylaziridines undergo ring expansion to azetidines with inversion at one carbon. Thus, cis-substituted aziridines give trans-azetidines and vice versa: Tetrahedron, 45, 1851 (1989):
Review of the chemistry of sulfonium ylides: Russ. Chem. Rev., 50, 481 (1981). Extensive review of the synthetic applications of dimethylsulfoxonium methylide: Tetrahedron, 43, 2609 (1987).
Sathishkumar, S.; Mahasampathgowri, S.; Balasubramanian, K. K.; Saiganesh, R. A convenient synthesis of dialkyl 2-(2-haloethylidene)malonates, cyanoacetates and halocrotonates by one carbon extension. Tetrahedron Lett. 2015, 56 (26), 4031-4035.
Kagawa, N.; Suzuki, M.; Kogure, N.; Toume, K. Characterization of organic iodides with iodine-127 nuclear magnetic resonance spectroscopy. Tetrahedron Lett. 2015, 56 (42), 5795-5798.
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.