posted on 2022-09-02, 20:44authored byJorge Escorihuela, Lawrence M. Wolf
The Co2(CO)8-mediated intramolecular
Pauson–Khand
reaction is an elegant approach to obtain cyclopentenone derivatives
containing asymmetric centers. In this work, we employed density functional
theory calculations at the M11/6-311+G(d,p) level of theory to investigate
the mechanism and reactivity for the Pauson–Khand reaction
of fluorinated and asymmetric N-tethered 1,7-enynes.
The rate-determining step was found to be the intramolecular alkene
insertion into the carbon–cobalt bond. The stereoselectivity
of the alkene insertion step was rationalized by the different transition
states showing the coordination of the alkene through the Re- and Si-face. The effects of different
fluorine groups and steric effects on both the alkenyl and alkynyl
moieties were also theoretically investigated.