5-tosylimino

Kinetic experiments show that the rate of thermal decomposition of 4-benzyl-5-tosylimino-AM,2,3,4-thiatriazoline is not influenced by the presence of enamines (the first-order rate constant is 42 x 10 5 s l in CC14 at 60°) excluding attack of alkene on the thiatriazoline with simultaneous loss of nitrogen.65 Instead, this result indicates formation of a discrete intermediate, which apparently is either the thiaziridine (19) and/or the 1,3-dipolar species (20) [Eq. (24)]. 

Dimethyl-3,6-dihydro-2,5(l//,4//)-pyrazinedithione (32) and p-toluenesul-fonyl azide gave a separable mixture of 1,4-dimethyl-5-tosylimino-3,4,5,6-tetrahydro-2(l//)-pyrazinethionc (33) and l,4-dimethyl-2,5-bistosylim-inopiperazine (34) [xylene, 130°C —> reflux, 12 h ( ) 35 and 13%, respectively).1362... 

Thermolysis of 3-benzyl-5-tosylimino-l,2,3,4-thiatriazoline (49) in the presence of thione (50) furnished 1,2,4-dithiazolidine-5-imine (51) in moderate yield. These results have been interpreted in terms of an unstable thiaziridineimine intermediate (48) which is trapped by the C=S compound in a regiospecific manner as depicted in Scheme 9 (76JHC883). Thermolysis without the presence of the thione (50) leads to the isolation of the sulfonyl carbodiimide (52). 

C11H13NO5S, 3-Methyl-2,4-dicarbomethoxy-A -cephem, 40B, 348 Cl1H13N3O2S2, 2,4-Dimethy1-5-tosylimino-A -1,2,3-thiadiazoline, 44B, 359... 

When 4-benzyl-5-tosylimino-l,2,3,4-thiatriazole 88 is heated in solution (chloroform at 60 °C) in the presence of ketenimines the [3+2] cycloadducts 89 are obtained in 51-70 % yields . 

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