Symmetrically H-Bridged Dimer of 2-Carboxylatobenzenediazonium. The 1:1 Complex between 2-Carboxybenzenediazonium Chloride and Benzenediazonium-2-carboxylate
The two zwitterions in the H-bridged dimer of 2-carboxylatobenzenediazonim (1) are linked by a crystallographically symmetric O⋯Hctdot;O hydrogen bond with an O⋯O distance of 2.436 (3) Å. Comparison of the (1) with the other benzenediazonium salts shows that the phenyl ring distortions in (1) are determined primarily by the diazonium substituent with only modest additional effects by the carboxylato group. Intramolecular neighboring goup interactions between the N2 group and the orthoCOO(H) group are indicated and are discussed. The terminal N atom of the diazonium group is bent away from the neighboring carboxylato group. The N2 and the carboxylato group are on the opposite sides of the best plane of the aromatic ring. Importantly, the carboxylato group is not fully conjugated with the aromatic ring but instead is rotated 6.5 (2)° around the C-CO2 axis in a fashion that suggest minimization of intramolecular repulsion between Nα and the proximate O atom and optimization of the inter-molecular hydrogen bonding
