Prall, M.M.PrallWittkopp, A.A.WittkoppFokin, Andrey A.Andrey A.FokinSchreiner, Peter R.Peter R.Schreiner2018-11-072018-11-072001https://resolver.sub.uni-goettingen.de/purl?gro-2/18194The effects of several substituents (-BH2, -BF2, -AlH2, -CH3, -C6H5, -CN, -COCH3, -CF3, -SiH3, -NH2, -NH3+, -NO2, -PH2, -OH, -OH2+, -SH, -F, -Cl, -Br) on the Bergman cyclization of (Z)-1,5-hexadiyne-3-ene (enediyne, 3) were investigated at the Becke-Lee-Yang Parr (BLYP) density functional (DFT) level employing a 6-31G basis set. Some of the substituents, (-NH3+, -NO2, -OH, -OH2+, -F, -Cl, -Br) are able to lower the barrier (up to a minimum of 16.9 kcal mol(-1) for difluoro-enediyne 7rr) and the reaction enthalpy (the cyclization is predicted to be exergonic for -OH2+ and -F) compared to the parent system giving rise to substituted 1,4-dehydrobenzenes at physiological temperatures. (C) 2001 John Wiley & Sons, Inc.journal_article10.1002/jcc.1114000170770800029