Nonstatistical Dynamic Effects in the Thermal C-2-C-6 Diels-Alder Cyclization of Enyne-Allenes


SAMANTA D., Cinar M. E. , DAS K., Schmittel M.

JOURNAL OF ORGANIC CHEMISTRY, vol.78, no.4, pp.1451-1462, 2013 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 78 Issue: 4
  • Publication Date: 2013
  • Doi Number: 10.1021/jo302524a
  • Title of Journal : JOURNAL OF ORGANIC CHEMISTRY
  • Page Numbers: pp.1451-1462

Abstract

The Diels-Alder (DA) reaction channel of the thermal C-2-C-6 (Schmittel) cyclization of enyne-allenes is studied computationally and experimentally evaluating the influence of temperature on product ratios. Remote substituents at the alkyne terminus influence the mechanism of the C-2-C-6/DA cyclization steering it either to a stepwise or a concerted course. Temperature independent product ratios, selectivity of product formation, and computational results obtained at (U)BLYP/6-31G(d) level unveil a mechanism that is strongly controlled by nonstatistical dynamics.