meta-Oligoazobiphenyls - synthesis via site-selective Mills reaction and photochemical properties.

Beilstein J Org Chem

University of Basel, Department of Chemistry, St. Johanns-Ring 19, 4056 Basel, Switzerland.

Published: September 2012

The investigation of multi-photochromic compounds constitutes a great challenge, not only from a synthetic point of view, but also with respect to the analysis of the photochemical properties. In this context we designed a novel strategy to access meta-oligoazobiphenyls via site-selective Mills reaction and Suzuki cross-coupling in a highly efficient iterative way. Photochemical examination of the resulting monomeric and oligomeric azo compounds revealed that the overall degree of switching was independent of the connected azo-units. However, one of the azobonds in the bis-azobiphenyl is isomerized preferentially despite the high structural similarity.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3388877PMC
http://dx.doi.org/10.3762/bjoc.8.99DOI Listing

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meta-Oligoazobiphenyls - synthesis via site-selective Mills reaction and photochemical properties.

Beilstein J Org Chem

September 2012

University of Basel, Department of Chemistry, St. Johanns-Ring 19, 4056 Basel, Switzerland.

The investigation of multi-photochromic compounds constitutes a great challenge, not only from a synthetic point of view, but also with respect to the analysis of the photochemical properties. In this context we designed a novel strategy to access meta-oligoazobiphenyls via site-selective Mills reaction and Suzuki cross-coupling in a highly efficient iterative way. Photochemical examination of the resulting monomeric and oligomeric azo compounds revealed that the overall degree of switching was independent of the connected azo-units.

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