Matrix isolation photochemistry: photoequilibrium between transient o-benzyne, carbon monoxide and transient cyclopentadienylideneketene in an argon matrix

Abstract

A photochemical study of benzocyclobutenedione is presented using narrow-band excitation and time-dependent spectroscopic measurements. Various photointermediates and the title photoequilibrium are firmly established. The UV/VIS absorption spectra of pure o-benzyne (1) and cyclopentadienylideneketene (4) are given. The results prove that the IR band at 2087 cm-1 previously ascribed to 1 and assigned to the {A figure is presented} vibration is instead the ketene band of 4. © 1990.