A Chiral Cyclotrisazobiphenyl: Synthesis and Photochemical Properties

Department of Chemistry, University of Basel, St. Johanns-Ring 19, CH-4056 Basel, Switzerland.
Organic Letters (Impact Factor: 6.36). 11/2011; 13(21):5908-11. DOI: 10.1021/ol202556z
Source: PubMed


A chiral cyclotrisazobiphenyl macrocycle was synthesized conveniently in three steps from the literature known 3,3'-diaminobimesityl in 37-38% overall yield. Irradiation with 302 nm, 365 nm or visible light allows access to different photostationary states (PSSs). These PSSs can be conveniently read out by CD-spectroscopy as each of them exhibits a positive, a negative, or no signal, respectively, at 275 nm.

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