title: Tuning photoinduced processes of covalently bound isoalloxazine and anthraquinone bichromophores.
abstract: We present here the synthesis of several new isoalloxazine cyclophanes containing electroactive anthraquinones linked by aliphatic chains of different lengths. Such structural changes provide different interchromophoric orientations leading to the tuning of the rate of the photoinduced electron transfer process from the anthraquinone unit towards the isoalloxazine singlet excited state. Molecular modelling studies were undertaken in order to determine the minimal energy of the proposed structures using Monte Carlo calculations (Amber, Macromodel v.8.1). The compounds have been fully characterised by NMR spectroscopy and the solid state structures of some of the macrocycles have been elucidated. The photophysical studies have been carried out in order to investigate the influence of π-π stacking on the optical properties of the macrocycles.
authors: Departamento de Química Orgánica y Bio-Orgánica, Facultad de Ciencias, Universidad Nacional de Educación a Distancia, Paseo Senda del Rey 9, 28040 Madrid, Spain. afarran@ccia.uned.es
authors: Angeles
authors: A
authors: Farrán
authors: John
authors: J
authors: Mohanraj
authors: Guy J
authors: GJ
authors: Clarkson
authors: Rosa M
authors: RM
authors: Claramunt
authors: Fernando
authors: F
authors: Herranz
authors: Gianluca
authors: G
authors: Accorsi
mesh_terms: D000880:Anthraquinones / Q000138:chemical synthesis / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004579:Electron Transport; D005415:Flavins / Q000138:chemical synthesis / Q000737:chemistry*; D047028:Macrocyclic Compounds / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D009010:Monte Carlo Method; D013053:Spectrophotometry
chemical_list: D000880:Anthraquinones; D005415:Flavins; D047028:Macrocyclic Compounds; C008173:isoalloxazine