Collect. Czech. Chem. Commun. 2003, 68, 1572-1578

Rotational Spectrum of 2,3-Benzofuran

B. Michela Giuliano and Walther Caminati*

Dipartimento di Chimica "G. Ciamician", Università di Bologna, Via Selmi 2, 40126 Bologna, Italy


The rotational spectra of the ground state and of one vibrational satellite of 2,3-benzofuran have been measured by millimetre-wave absorption free jet spectroscopy in the frequency range 60-78 GHz. The value of the inertial defect (-0.072 uÅ2) shows the molecule to be planar. The shifts of the rotational constants in going from the ground to the excited state indicate that the observed vibrational satellite does not belong to the two lowest energy motions, the butterfly and 1,3-ring-twisting, which undergo relaxation upon the supersonic expansion.

Keywords: Rotational spectroscopy; Free jets; Vibrational relaxation; Benzofurans; Oxygen heterocycles.

References: 21 live references.