Remarkably variable reaction modes of frustrated Lewis pairs with non-conjugated terminal diacetylenes.
The frustrated Lewis pair P(o-tolyl)(3)/B(C(6)F(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(6)F(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.
Chen
Chao
C
Organisch-Chemisches Institut, Westfälische Wilhelms-Universität, Corrensstrasse 40, 48149 Münster, Germany.
Fröhlich
Roland
R
Kehr
Gerald
G
Erker
Gerhard
G