Posts Tagged ‘Houk and co’

The direct approach is not always the best: butadiene plus dichlorocarbene

Wednesday, September 19th, 2012

The four-electron thermal cycloaddition (in reverse a cheletropic elimination) of dichlorocarbene to ethene is a classic example of a forbidden pericyclic process taking a roundabout route to avoid directly violating the Woodward-Hoffmann rules. However, a thermal six-electron process normally does take the direct route, as in for example the Diels-Alder cycloaddition as Houk and co have recently showed using molecular dynamics[1]. So can one contrive a six-electron cycloaddition involving dichlorocarbene?



  1. K. Black, P. Liu, L. Xu, C. Doubleday, and K.N. Houk, "Dynamics, transition states, and timing of bond formation in Diels–Alder reactions", Proceedings of the National Academy of Sciences, vol. 109, pp. 12860-12865, 2012.