Are vinylidenes possible intermediates in thermal rearrangements of substituted cyclopropenes? A theoretical study

The thermally induced ring-opening reactions of substituted cyclopropenes t o the corresponding vinylidenes have been investigated computationally; the alkyl-substituted singlet vinylidenes have been found to lie in potential wells of 7-11 kcal mol(-1) (DFT calculations; 1 kcal = 4.184 kJ).