Variation of the backbone conjugation in NLO model compounds : torsion-angle-restricted, biphenyl-based push-pull-systems

Rotzler, Jürgen and Vonlanthen, David and Barsella, Alberto and Boeglin, Alex and Fort, Alain and Mayor, Marcel. (2010) Variation of the backbone conjugation in NLO model compounds : torsion-angle-restricted, biphenyl-based push-pull-systems. European Journal of Organic Chemistry, 2010 (6). pp. 1096-1110.

Full text not available from this repository.

Official URL: http://edoc.unibas.ch/dok/A5262485

Downloads: Statistics Overview


Terminal piperidinyl- and nitro-functionalized biphenyls, bridged between the 2 and 2prime positions by a variable number of methylene groups, are synthesized and fully characterized. These push-pull systems with defined and restricted torsion angles between their phenyl rings are ideal model compounds to investigate the influence of the chromophore's conjugation in nonlinear optic (NLO) responses. A general synthetic route that can be implemented to access these model compounds is reported, starting from dibromo or ditriflate biphenyls. Hartwig-Buchwald cross-coupling, a selective azacycloalkylation of diaminobiphenyls and a mild oxidation of primary amines to nitro groups in the presence of a tertiary amine summarizes the synthetic pathway towards the desired model compounds. NLO properties of the series of torsionally constrained push-pull biphenyls are collected by electric-field-induced second-harmonic generation (EFISH) experiments. The results agree qualitatively with semi-empirical simulations based on the AM1 Hamiltonian. A linear dependence of the quadratic response on the cos2(Phi) of the inter-aryl dihedral angle is observed, which points to oscillator strength loss as the dominant effect of increasing backbone twist.
Faculties and Departments:05 Faculty of Science > Departement Chemie > Chemie > Molecular Devices and Materials (Mayor)
UniBasel Contributors:Mayor, Marcel and Vonlanthen, David
Item Type:Article, refereed
Article Subtype:Research Article
Note:Publication type according to Uni Basel Research Database: Journal article
Identification Number:
Last Modified:05 Apr 2017 13:44
Deposited On:22 Mar 2012 14:06

Repository Staff Only: item control page