title: Photochromic Dithienylethene-Containing Boron(III) Ketoiminates: Modulation of Photo-Responsive Behavior through Variation of Intramolecular Motion.
abstract: A series of dithienylethene-containing boron(III) ketoiminates, as well as their corresponding β-ketoimine ligands, have been synthesized and characterized. The photophysical, electrochemical, and photochromic properties of the compounds have been studied. Photocyclization has been found to be suppressed upon introduction of a phenyl substituent on the nitrogen atom of the β-ketoiminate core, whereas photochromism could be observed by replacement of the phenyl substituent with a bulky mesityl group. It is believed that the steric effect of the mesityl unit restricts molecular rotation, resulting in such a prominent difference in the photochromic properties.
authors.affiliation: Institute of Molecular Functional Materials, (Areas of Excellence Scheme, University Grant Committee (Hong Kong)) and, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
authors.forename: Cheok-Lam
authors.initials: CL
authors.lastname: Wong
authors.affiliation: Institute of Molecular Functional Materials, (Areas of Excellence Scheme, University Grant Committee (Hong Kong)) and, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China.
authors.forename: Chun-Ting
authors.initials: CT
authors.lastname: Poon
authors.affiliation: Institute of Molecular Functional Materials, (Areas of Excellence Scheme, University Grant Committee (Hong Kong)) and, Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China. wwyam@hku.hk.
authors.forename: Vivian Wing-Wah
authors.initials: VW
authors.lastname: Yam
keywords: boron; heterocycles; ketoiminates; photochromism; steric effects