Highly fluorescent complexes with 3-isocyanoperylene and N-(2,5-di-tert-butylphenyl)-9-iso cyano-perylene-3,4-dicarboximide

• Published in: Dalton transactions : an international journal of inorganic chemistry 2014-06, Vol.43 (28), p.10885-10897
• Main Authors: Lentijo, S, Exposito, JE, Aullon, G, Miguel, JA, Espinet, P
• Format: Article
• Language: English
• Subjects: Chromium; Derivatives; Emission; Fluorescence; Fragmentation; Maxima; Molecular orbitals; Orbitals
• ISSN: 1477-9226; 1477-9234
• DOI: 10.1039/c4dt01016g

The perylene derivatives 3-isocyanoperylene (Per-N&z.tbd; C) (4a) and N-(2,5-di-tert-butylphenyl)-9-iso cyano-perylene-3,4-dicarboximide (PMI-N&z.tbd; C) (4b) were prepared and used to synthesize gold complexes [AuX(CNR)] (X = C sub(6)F sub(5) (5a,b), C sub(6)F sub(4)-O super(n)Bu-p(6b) ). The reaction of 5b and 6b with HNEt sub(2) led to the carbene complexes [AuX{C(NEt sub(2))(NHR)}] (7b, 8b), respectively. The molecular structure of complexes 7b and 8b have been determined by X-ray diffraction analysis showing intermolecular pi -stacking of the perylene groups and C sub(6)F sub(5) rings and no Au...Au interactions. The derivative compounds [M(CO) sub(5)(CNR)] (M = Cr (9a,b), Mo (10a,b) or W (11a,b)) and trans-[Pd(CNR) sub(2)(C sub(6)F sub(3)Cl sub(2)) sub(2)] (12a,b) were also prepared. All complexes exhibit fluorescence associated with the perylene fragment with emission quantum yields, in solution at room temperature, in the range 0.05-0.93 and emission lifetimes similar to 4 ns. DFT calculations were performed of the absorption spectra of the ligands Per-N&z.tbd; C and PMI-N&z.tbd; C and representative complexes [Au(C sub(6)F sub(5))(CNR)], [Cr(CO) sub(5)(CNR)], showing a perylene-dominated intraligand pi - pi * emissive state, from the HOMO and LUMO orbitals of the perylene chromophore, but with significantly different absorption maxima by the influence of the metal fragment, particularly significant in the Per-N&z.tbd; C derivatives.