Synthesis and characterization of tetraphenylammonium salts.

The phenyl (Ph) group is a representative substituent in the field of organic chemistry as benzene (the parent molecule) is of fundamental importance. Simple Ph-substituted compounds of common chemical elements are well known. However, extensive structural characterization of tetraphenylammonium (PhN) salts has not been reported. Herein, the synthesis of PhN salts and their characterization data including the H and C nuclear magnetic resonance (NMR) spectra and the single-crystal X-ray structure have been presented. An intermolecular radical coupling reaction between an aryl radical and a triarylammoniumyl radical cation was conducted to synthesize the target moieties. The PhN salts described herein are the simplest tetraarylammonium (ArN) salts known. The results reported herein can potentially help access the otherwise inaccessible non-bridged ArN salts, a new class of rigid and sterically hindered organic cations.