POLYSULFONYLAMINE: TEIL LXXIV.1N-(ORGANYLOXYCARBONYL)-DIMESYLAMINE (N,N-DIMESYLCARBAMATE): ERSTSYNTHESE UND AUSGEWÄHLTE FESTKÖRPERSTRUKTUREN

Abstract

Abstract Carbamates containing an N,N-disulfonylamino moiety (RSO2)2N—are reported for the first time. The compounds (MeSO2)2N—C(O)—OR, where R = CICH2, MeCHCl, ClCH2CH2, BrCH2CH2, Cl3CCH2 or Ph, were obtained in good yields by treating the corresponding chloroformates with Me3SiN(SO2Me)2 in CH2Cl2 at room temperature in the presence of a catalytic amount of pyridine. Under the same conditions, methyl chloroformate afforded a mixture of (MeSO2)2N—Me and (MeSO2)2N—C(O)—OMe (1a), whereas benzyl chloroformate was quantitatively decarboxylated to give (MeSO2)2N—Bz and higher alkyl chloroformates (R = Et, “Bu, ′Bu) were found to be unreactive. Metathesis of (MeSO2)2NAg with chloroformates in MeCN solution at room temperature is an extremely sluggish process and generally unsuitable for synthetic purposes; however, the carbamate (MeSO2)2N—C(O)—OCCl3 (1c), which could not be obtained via the Me3SiCl elimination reaction, was isolated in moderate yield by the silver salt method. The crystal structures of 1a (monoclinic, space group P21/c, two independent molecules) and 1c (monoclinic, P21/c) were determined by low-temperature X-ray diffraction. The most important result is the weakened S2N—C(O) bond as indicated by the N—C bond lengths 144.3 and 144.6 pm in 1a and 141.3 pm in 1c. In both compounds, the nitrogen and carbon atoms of the carbamoyl groups have a trigonal-planar environment; the trigonal planes are tilted at interplanar angles of 62.0 and 49.5° in 1a and 48.1° in 1c.