Premium
Polar Liquid Crystals Derived from Sulfonium Zwitterions of the [closo‐1‐CB11H12]– Anion
Author(s) -
Pecyna Jacek,
Żurawiński Remigiusz,
Kaszyński Piotr,
Pociecha Damian,
Zagórski Piotr,
Pakhomov Serhii
Publication year - 2016
Publication title -
european journal of inorganic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.667
H-Index - 136
eISSN - 1099-0682
pISSN - 1434-1948
DOI - 10.1002/ejic.201600240
Subject(s) - sulfonium , chemistry , dipole , polar , ion , liquid crystal , dielectric , crystallography , organic chemistry , salt (chemistry) , physics , optoelectronics , astronomy , optics
A series of substituted 12‐sulfonium zwitterions 1[ n ] and one example of a 1‐sulfonium analogue 2[5]a were prepared in four steps. Derivatives 1[ n ] exhibit rich crystalline polymorphism and a high‐temperature SmB cry phase stabilized by dipolar interactions. Solution studies in a nematic host demonstrated positive dielectric anisotropy of compounds 1[5]a – 1[5]c (Δ ε ≈ +18 extrapolated from 8 mol‐% solutions) resulting from a longitudinal electric dipole moment of ca. 9.5 D. The effectiveness of additives 1[5] was analyzed by using the Maier–Meier formalism and DFT methods and compared to those of more polar derivatives 3[6]a and Pyr[10] .