Proton-triggered octopolar NLO chromophores.
C(3)-symmetric, octopolar 1,3,5-alkynylbenzenes with terminal pyridyl substituents are presented which show an increase up to 17-fold in the second-order NLO activity upon protonation while maintaining their octopolar character, as confirmed by the depolarization ratios measured.
Asselberghs
Inge
I
Department of Chemistry, University of Leuven, Celestijnenlaan 200 D, 3001 Leuven, Belgium.
Hennrich
Gunther
G
Clays
Koen
K