Role of triplet states of aryldiazonium cations in the Meerwein reaction

The mechanism of the Meerwein reaction was interpreted on the basis of quantum-chemical calculations of the optimal geometry, electronic spectra, and ground state of a large number of diazonium cations. The relationship of this process with the triplet excited state of aryldiazonium cations and the role of spin catalysis in thermal excitation of these states via ligand-to-metal and metal-to-ligand electron transfer involving organic ligands and complex copper chlorides as catalysts were examined.