A new class of enantiopure ortho,ortho-disubstituted azobenzene photoswitches has been synthesized from (S)-2-(p-tolylsulfinyl)benzoquinone and arylhydrazines. The sulfoxide acts as a unidirectional controller of the helical chirality that arises in the Z isomer. Highly congested E-azobenzenes showed two atropisomeric diastereoconformers in the solid state that converged upon irradiation into a unique Z isomer with defined helicity (M), as evident in the X-ray structure and circular dichroism spectroscopy. Complementary to the classical azobenzenebased switches, the photoswiching event is promoted under green/blue light and does not occur under UV irradiation.
Titolo: | CONTROL OF THE HELICAL CHIRALITY OF ENANTIOPURE SULFINYL (Z)-AZOBENZENE-BASED PHOTOSWITCHES |
Autore/i: | I. Nunez; E. Merino; M. Lecea; PIERACCINI, SILVIA; SPADA, GIAN PIERO; C. Rosini; G. Mazzeo; M. Ribagorda; M. C. Carreno |
Autore/i Unibo: | |
Anno: | 2013 |
Rivista: | |
Digital Object Identifier (DOI): | http://dx.doi.org/10.1002/chem.201203243 |
Abstract: | A new class of enantiopure ortho,ortho-disubstituted azobenzene photoswitches has been synthesized from (S)-2-(p-tolylsulfinyl)benzoquinone and arylhydrazines. The sulfoxide acts as a unidirectional controller of the helical chirality that arises in the Z isomer. Highly congested E-azobenzenes showed two atropisomeric diastereoconformers in the solid state that converged upon irradiation into a unique Z isomer with defined helicity (M), as evident in the X-ray structure and circular dichroism spectroscopy. Complementary to the classical azobenzenebased switches, the photoswiching event is promoted under green/blue light and does not occur under UV irradiation. |
Data prodotto definitivo in UGOV: | 2014-12-09 16:33:04 |
Appare nelle tipologie: | 1.01 Articolo in rivista |