Preparation and Structure of Sulphimides

Sulphimides. Several new procedures for the preparation of sulphimides have been published. Sulphonamides, on treatment with DMSO and oxalyl chloride, can be converted into the corresponding A -substituted sulphimides ArS02N=SMej. This reaction can be applied to compounds containing substituents having strong electron-withdrawing effects, e.g. sulphonyl or /j-nitrophenyl. Various thietan derivatives (31), such as sulphoxides, sulphimides, sulphonium salts, and sulph-oximides, have been prepared with dry Chloramine-T, and their isomers separated.  

Another improved synthesis of various symmetric and unsymmetric N-(toluene-p-sulphonyl)-sulphimides is by the treatment of the sulphides with solid Chloramine-T under phase-transfer catalytic conditions, using tetrabutylammonium salts as the catalyst, in CH2CI2. 5-Vinyl-sulphimides can be prepared by the following three methods (a) treatment of vinyl sulphides with Chloramine-T, b) base-catalysed elimination of HCl from 2-(halogenoethyl)aryl-sulphimides, and (c) elimination of acetic acid from / -acetoxy-sulphimides with bases. JV-2,4-Dinitrophenyl-S5-dimethylsulphimide (32) can be prepared by the sequential treatment of DMSO with PjOj in DMF, then with 2,4-dinitroaniline, and finally 

The copper-catalysed thermolysis of toluene-/)-sulphonyl azide in the presence of various sulphides also affords the corresponding sulphimides. A kinetic study on the reactions of Chloramine-T with orrAo-substituted sulphides indicates a marked steric hindrance by or//ro-substituents, while the anchimeric effect of ortho-groups that have a carbonyl function decreases in the order CHjCOjH CH COjMe CH COj- COjMe COJti COr- 

Ethoxycarbonylnitrene (generated photochemically from the azide) also reacts with 4-t-butylthian, affording a nearly 1 1 mixture of both cis- and trans-sulphimides. This non-stereoselectivity in the reaction of the nitrene is in marked contrast with that of the reaction of carbenes with the thian the thian reacts with both bis(alkoxycarbonyl)- and bis(diacetyl)-carbenes, giving the trans-yMes as the sole products (see Vol. 4, p. 112). Various sulphimides of cyclic sulphides, e.g. thians, cis- and frans-thiadecalins, oxathians, and dithians, can be prepared by treating the sulphides either with anilines and AT-chlorosuccinimide or with Bu OCl. In this reaction, the formation of (33 R = Bu , = /7-ClCjH4) with an equatorial 

---