Cross-Conjugation vs. Linear Conjugation in Donor-Bridge-Acceptor Nitrophenol Chromophores
作者:Mikkel Andreas Christensen、Eduardo Antonio Della Pia、Jørgen Houmøller、Sean Thomsen、Marius Wanko、Andrew D. Bond、Angel Rubio、Steen Brøndsted Nielsen、Mogens Brøndsted Nielsen
DOI:10.1002/ejoc.201301642
日期:2014.4
The influence of cross-conjugationvs. linearconjugation on the electronic communication between donor and acceptor groups in phenol(ate)–bridge–nitrobenzene chromophores was investigated by solution and gas-phase absorption spectroscopy, fluorescence spectroscopy, and quantum chemical calculations. The compounds studied include, among others, geminally and trans-substituted diethynylethenes prepared
Synthesis and Characterization of Tetrathiafulvalene-Substituted Di- and Tetraethynylethenes with <i>p</i>-Nitrophenyl Acceptors
作者:Asbjørn S. Andersson、Lasse Kerndrup、Anders Ø. Madsen、Kristine Kilså、Mogens Brøndsted Nielsen、Philip R. La Porta、Ivan Biaggio
DOI:10.1021/jo802190q
日期:2009.1.2
Novel di- and tetraethynylethene (DEE and TEE) compounds functionalized with tetrathiafulvalene (TTF) donor groups and p-nitrophenyl acceptor groups were synthesized by palladium-catalyzed cross-coupling reactions under various conditions. The molecules are strong chromophores and were investigated for their optical properties. Placement of two TTFs and two p-nitrophenyls about a central TEE core provides a molecule with a high third-order optical nonlinearity. The molecules experience reversible oxidations of the TTF units, and the optical properties of the oxidized species were elucidated by spectroelectrochemistry. The degree of quinoid character of the p-nitrophenyl in the molecules was determined by X-ray crystallography.
Synthesis and Characterization of Extended Tetrathiafulvalenes with Di-, Tri-, and Tetraethynylethene Cores
A selection of new acetylenic buildingblocks has been prepared and employed for construction of extended tetrathiafulvalenes (TTFs) and novel donor–acceptor molecules based on either diethynylethene (DEE), triethynylethene (TriEE), or tetraethynylethene (TEE) cores. The novel chromophores were studied for their redox, chromophoric, and structural properties, which have provided fundamental structure–property