Generation and Characterization of p-Phenylene Bis(carbenes). Spectroscopic Studies and Theoretical Calculations

Abstract

para-Phenylene(carbeno)halocarbenes, consisting of both ground state triplet carbene unit(:CH) and ground state singlet halocarbene unit (:CX, X=Cl,Br,F) at para-position of benzene ring, were generated by photolysis of the corresponding nitrogenous precursors in Ar matrix at 13K. The structure and ground state multiplicity of the species were investigated by FT-IR and UV/vis spectroscopy in combination with DFT calculation. Effect of the nature of halogen on the relative energies for each electron configurations was also examined.