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Das nach Literatur dargestellte Amin (I) geht mit 2 Mol NOBF4 in Propionitril in das Dikation (II) über, das zum bekannten Sulfoxid (IV) hydrolysiert werden kann.

When disulfides are cleaved by aqueous iodine, neighboring group participation facilitates the rate of reaction and the formation of cyclized products. The series of bis-disulfides [X(CH2)3S]2 was prepared, X = N(CH3)2, 1, NH2, 2, N(CH3)3+, 3, as well as [NH2(CH2)4S]2, 4. The tertiary amine, 1, is oxidized by aqueous I2 at a rate which is accelerated by as much as 106 over the rate of reaction of the quaternary ammonium iodide salt 3. The oxidation products of 1 are the sulfinic and sulfonic acids while 3 yields the sulfonic acid. Aqueous iodine reacts with the primary amines 2 and 4 at moderately accelerated rates to give the cyclic sulfinamides, isothiazolidine 1-oxide from 2 and tetrahydro-1,2-thiazine 1-oxide from 4. This oxidative cyclization reaction is the most direct route to these cyclic sulfinamides. At a given pH, the rate law for the oxidation of 1 and 2 is -d[RSSR]/dt = -fe[RSSR][y. At high pH, compound 4 has the same rate law. The kinetic data for 4 at low pH and for 3 resemble those reported in a classical study of the aqueous iodine oxidative cleavage of cystine.2 The kinetics and mechanisms of these reactions will be discussed.

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The kinetics of the aqueous iodine oxidation of a number of imidazolyl-and benzimidazolylalkyl methyl sulfides have been studied. Evidence of neighboring-group participation has been observed in all cases. The anchimeric assistance provided by the benzimidazole moiety is evidenced by rate accelerations of 102-106. The oxidation of l-methyl-2-[3-(methylthio)propyl] imidazole, 1, is 106 times faster than that of simple thioethers and is faster than any previously reported acyclic thioether. The reaction of 2-[3-(methylthio)propyl]benzimidazole is accelerated by 10s via a transient N-S dication. Additionally, the pH profiles of all of the compounds studied provide strong evidence for N-S interacted intermediates.