Secondary Bonding as a Force Dictating Structure and Solid-State Aggregation of the Primary Nitrene Sources (Arylsulfonylimino)iodoarenes (ArINSO₂Ar‘)

Abstract

Iodonium ylides of the form ArINSO2Ar‘ (Ar = m-tolyl, Ar‘ = p-nitrophenyl (1); Ar = m-tolyl, Ar‘ = phenyl (2); Ar = m-tolyl, Ar‘ = p-tolyl (3); Ar, Ar‘ = p-tolyl (4)) have been prepared and crystallographically characterized. Comparisons to previously structurally characterized members of this class of materials (PhINTs (Ts = p-toluenesulfonyl), o-TolylINTs, MesINTs) demonstrate that apparently minor perturbations of the aromatic rings have substantial consequences on the supramolecular assemblies of these materials. The structures range from zig−zag polymers (PhINTs, MesINTs), linear polymers (o-TolylINTs), layered structures (1), two-dimensional ladders (2, 3, o-TolylINTs), to even three-dimensional stepladders (4). Ab initio calculations for a model molecule, PhINSO2Ph, corroborate the presence of a I−N single bond and show considerable charges being localized on the I, N, S, and O atoms (+, −, +, and − charges, respectively). Extensive attractive networks of I···O and I···N secondary bonds thus dominate the solid-state polymers. Within the monomeric units of ArINSO2Ar‘, a U-turn-shaped motif is observed. This structural shape appears to optimize secondary bonding contacts between charged INSO2 arrays. The structures of ArINSO2Ar‘ have been systematically characterized.