\The N-substituted carbamates RSOzCHR'NRC and

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1‐Tosylalkyl isocyanates, p‐CH3C6H4SO2CHRNCO (II), have been prepared in good yields from the reaction of S‐ethyl N‐(1‐tosylalkyl)thiocarbamates (I) and chlorine in a heterogeneous mixture of dichloromethane and aqueous sodium hydrogen carbonate. The reaction probably involves the intermediate formation of the previously unreported N‐(1‐tosylalkyl)carbamoyl chlorides, p‐CH3C6H4SO2CHRNR′COCl (IV), which may be isolated in high yield under anhydrous reaction conditions. In mildly alkaline solutions, these carbamoyl chlorides (R′  H) are smoothly converted into the 1‐tosylalkyl isocyanates. Ethanesulfonyl N‐methyl‐N‐(tosylmethyl)formamide (V), obtained by oxidation of S‐ethyl N‐methyl‐N‐(tosylmethyl)thiocarbamate, p‐CH3C6H4SO2CH2N(CH3)C(O)SC2H5, with hydrogen peroxide in acetic acid, was treated with chlorine to give tosyl chloride and ethanesulfonyl chloride. α‐Oxosulfones, p‐CH3C6H4SO2CH2N(CH3)C(O)SO2C2H5, are therefore unlikely intermediates in the formation of N‐(1‐tosylalkyl)carbamoyl chlorides. The reaction of S‐ethyl N‐(1‐tosylalkyl)thiocarbamates (I) with bromine in CH2Cl2/NaHCO3‐H2O in the presence of methanol gives methyl N‐(1‐tosylalkyl) carbamates, a result which can be best interpreted by assuming 1‐tosylalkyl isocyanates as intermediates.

The carboxamides, p‐CH3C6H4SO2CHR′NR″COR′″, the sulfonamides, p‐CH3C6H4SO2CHR′NR″SO2C6H5, and the lactams, , have been prepared by condensation of p‐methylbenzenesulfinic acid with an aldehyde and a carboxamide, a sulfonamide, or a lactam, respectively. The scope of the reaction is discussed. Infrared and PMR spectral data of the condensation products are given.

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