The combination of carbaboranylmercuric chloride (new type of bulky Lewis acid) and silver triflate efficiently catalyzes cycloisomerization of 1, 3-dienes at room temperature. The catalytic system gives allyl-substituted azacycles and cycloalkanes in excellent yields with high to complete regioselectivity.
Hg(OTf)<sub>2</sub>-catalyzed Cycloisomerization of Aryl- and Hetero-substituted 1,3-Dienes
We developed Hg(OTf)2-catalyzed Friedel–Crafts-like cycloisomerization of 7-arylhepta-1,3-dienes to give propenyl-substituted tetrahydronaphthalenes in excellent catalytic turnover under very mild conditions. 1,3-Dienyl sulfonamides and 1,3-dienyl alcohols were also efficiently cyclized to afford heterocyclic compounds.