Remarkably variable reaction modes of frustrated Lewis pairs with non-conjugated terminal diacetylenes

摘要

The frustrated Lewis pair P(o-tolyl)_3/B(C_6F_5)_3 reacts with 1,7-octadiyne by acetylene C-C coupling to yield the zwitterionic product 2a. In contrast, the P(o-tolyl)_3/B(C_6F_5)_3 Lewis pair reacts with 1,6-heptadiyne by a sequence involving 1,1-carboboration of a terminal acetylene to eventually yield the heterocyclic product 4.