G. Maier et al., SMALL RINGS .82. CHLORINATED CYCLOPROPENYLIDENES, VINYLIDENECARBENES,AND PROPARGYLENES - IDENTIFICATION BY MATRIX-ISOLATION SPECTROSCOPY, Journal of the American Chemical Society, 116(5), 1994, pp. 2014-2018
Matrix-isolated mono- and dichlorocyclopropenylidene have been generat
ed by high-vacuum flash pyrolysis from di- and trichlorocyclopropenes.
By subsequent photolysis they have been isomerized to the correspondi
ng vinylidenecarbenes and propargylenes. The identification of six new
carbenes is based on the comparison of their experimental and calcula
ted (MP2/6-31G()) infrared spectra. All have singlet electronic groun
d states.