Polysulfonylamine Polysulfonylamine, CXXXVIII [1], 1.1-Di(organosu!fonyl)-3,3-diorganylharnstoffe: Synthese von acht Vertretern und Kristallstruktur des Prototyps (MeSO2)2N-C(O)-NMe2 / Polysulfonylamines, CXXXVIII [1]. 1.1-Di(organosulfonyl)-3,3-diorganylureas: Synthesis of Eight Representatives and Crystal Structure of the Prototype (MeSO2)2N-C(O)-NMe2

Abstract

Eight compounds of the type (RSO2)2N-C(O)-NR'2 , where R = Me or 4-tolyl and R' = Me, Et, iPr or Ph, were obtained in good yields by treating the corresponding carbamoyl chlorides R'2NC(0)C1 with silver salts AgN (SO2R)2 in acetonitrile solution. The pronounced sensitivity of the compounds towards atmospheric moisture is indicative of a high degree of electrophilic activation at the carbonyl centre; bulk hydrolysis rapidly leads to carbon dioxide and the corresponding ammonium salt R'2NH+ 2'N (SO2R)2. In the 1H and 13C NMR solution spectra, the R4N groups of the ureas give rise to distinct R' resonances at room temperature, reflecting unusually high barriers to rotation about the C(O)-NR'2 bonds. For ( MeSO2)2N-C(O)-NMe2 (1a) and the analogous ditosyl compound, the 1H NMR signals of the dimethylamino group were found to coalesce at 107 °C and 93 °C, respectively, which corresponds to a rotational barrier of ⊿G# c ≈ 80 kJ mol-1. In the crystal of la (triclinic, space group P1̄, Z = 2; X-ray diffraction at -75 °C), the molecule possesses an essentially planar Me2N-C(O)-N moiety (except H atoms), whereas the C-NS2 grouping is pyramidalized to such an extent that N lies 27.8(2) pm out of the plane defined by the carbonyl C atom and the two sulfonyl S atoms [S-N-S 120.52(11)°, C-N-S 115.73(14) and 115.06(14)°]. The most remarkable features of the molecular structure are the exceedingly long C(O)-NS2 bond [148.6(3) pm] and the concomitantly short C-O and C(O)-NC2 bonds [121.4(3) and 132.2(3) pm]. The crystal packing of la is governed by a three-dimensional network of nine intermolecular C-H···O hydrogen bonds originating from the activated M e-S and M e -N donor groups (H···O 230-266 pm, C-H···O 123-173°).