Trimethylsulfoxonium ylide, reaction with

Reaction of A,A-dimcthylsullamoyl aziridines 323 and 325 with primary amines furnishes substituted 1,2,5-thiadiazolidine 1,1-dioxides 324 and 326, respectively, in a regioselective manner <06SL833>. Aziridine 325 is made from ( I /t,6,S ,Z)-bicyclo[4.2. l]non-3-en-9-one in two steps /V,/V-dimethylsulfamoyl imine formation using dimethylsulfamide and subsequent reaction with trimethylsulfoxonium ylide. The product from the reaction with 4-methoxy-benzyl amine can be subsequently manipulated (debenzylation and derivatization) to give the alternative nitrogen substitution pattern in a controlled manner. 

A The epoxide can be prepared from cyclohexanone by reaction with the ylide derived from trimethylsulfoxonium iodide or in a... 

The reaction of epoxides (1) with trimethylsulfoxonium ylide leads to oxetanes (2) in high yields through a nucleophilic ring opening followed by intramolecular dimethylsulfoxide elimination (Eq. (1)) (83JOC5133). This is probably the simplest homologation reaction of a three-membered heterocycle. 

Vinylaziridine 7.6 Vinyl azide 5 (20 mmol) and trimethylsulfoxonium ylide (2 equiv) in DMSO was stirred at 20°C for 12 h. The reaction mixture wad diluted with Et20 (100 mL) and washed with water (5x100 mL). Evaporation of the solvent afforded triazoline 6 in 95% yield. Pyrolysis of 6 in refluxing PhMe (3 h) gave 7 in 65% yield alternatively flash vacuum pyrolysis (FVP) afforded 7 in 93% yield. 

The echoes of Corey s seminal discovery with sulfonium and sulfoxonium ylides have found considerable resonance in modern investigations of enan-tioselective cyclopropanation reactions. Shibasaki showed that treatment of pyrrole amides such as 126 with trimethylsulfoxonium ylide was effectively promoted by the La-Li-(biphenyldiolate) catalyst 127 to give the cyclopropane adduct 128 in 98% ee (Equation 20) [78]. Key to the success of the transformation was the use of Nal as an additive. The investigators speculated that exchange of Li for Na occurs in 127 to some extent to give an active cyclopropanation catalyst that is more enantioselective. The observation underscored the versatility of such bifunctional heterobimetallic catalysts, the properties of which can be fine-tuned in a multitude of ways by variation of the ligand and the nature of the metals employed [79]. 

Cyclic dinuclear ylide complexes have also been prepared with sulfur ylides. The reactions of (dppm)(AuCl)2 or (dppe)(AuCl)2 with trimethylsulfoxonium tetrafluoroborate and base under phase-transfer conditions gave the products shown in Scheme 42. Auration of the dppm ligand leads to the byproducts.27... 

Methylation of DMSO with methyl iodide yields trimethylsulfoxonium iodide (Scheme 14). This is an unusual reaction since other sulfoxides and halides form the products of O-alkylation. By treatment with strong bases, the trimethylsulfoxonium salt is converted into the sulfoxonium ylide (25) (Scheme 14). 

Scheme 6 Reaction of naltrexone methyl ether (22) with a stable sulfur ylide. Reagents and conditions (a) trimethylsulfoxonium iodide, NaH, THF, 55 °C to rt, 67%...

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