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

Iodonium ylides of the form ArINSO 2 Ar‘ (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, PhINSO 2 Ph, 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 ArINSO 2 Ar‘, a U-turn-shaped motif is observed. This structural shape appears to optimize secondary bonding contacts between charged INSO 2 arrays. The structures of ArINSO 2 Ar‘ have been systematically characterized.