Synthesis, Structure, and Luminescence of Di- and Trinuclear Palladium/Gold and Platinum/Gold Complexes with (2,7-Di-tert-butylfluoren-9-ylidene)methanedithiolate

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• 作者：José ; Vicente ; Pablo Gonz&aacute ; lez-Herrero ; Marí ; a Pé ; rez-Cadenas ; Peter G. Jones ; Delia Bautista
• 刊名：Inorganic Chemistry
• 出版年：2007
• 出版时间：May 28, 2007
• 年：2007
• 卷：46
• 期：11
• 页码：4718 - 4732
• 全文大小：319K
• 年卷期：v.46,no.11(May 28, 2007)
• ISSN：1520-510X

文摘

Acetone solutions of [Au(OClO₃)(PCy₃)] react with complexes [M{S₂C=(t-Bu-fy)}₂]^2- [t-Bu-fy = 2,7-di-tert-butylfluoren-9-ylidene; M = Pd (2a), Pt (2b)] or [M{S₂C=(t-Bu-fy)}(dbbpy)] [dbbpy = 4,4'-di-tert-butyl-2,2'-bipyridyl; M = Pd(3a), Pt (3b)] to give the heteronuclear complexes [M{S₂C=(t-Bu-fy)}₂{Au(PCy₃)}₂] [2:1 molar ratio; M = Pd (4a),Pt (4b)], [M{S₂C=(t-Bu-fy)}(dbbpy){Au(PCy₃)}]ClO₄ [1:1 molar ratio; M = Pd (5a), Pt (5b)], or [M{S₂C=(t-Bu-fy)}(dbbpy){Au(PCy₃)}₂](ClO₄)₂ [2:1 molar ratio; M = Pd (6a), Pt (6b)]. The crystal structures of 3a, 4a, 4b, 5b,and 6a have been solved by single-crystal X-ray studies and, in the cases of the heteronuclear derivatives, revealthe formation of short Pd···Au or Pt···Au metallophilic contacts in the range of 3.048-3.311 Å. Compounds 4aand b and 5a and b undergo a dynamic process in solution that involves the migration of the [Au(PCy₃)]⁺ unitsbetween the sulfur atoms of the dithiolato ligands. The coordination of 2a and b and 3a and b to [Au(PCy₃)]⁺ unitsresults in important modifications of their photophysical properties. The dominant effect in the absorption spectrais an increase in the energy of the MLCT (4a and b) or charge transfer to diimine (5a, b, 6a, b) transitions becauseof a decrease in the energies of the mixed metal/dithiolate HOMOs. The Pd complexes 2a and 4a are luminescentat 77 K, and the features of their emissions are consistent with an essentially metal-centered ³d-d state. The Pt/Aucomplexes are also luminescent at 77 K, and their emissions can be assigned as originating from a MLCT tripletstate (4b) or a mixture of charge transfer to diimine and diimine intraligand -* triplet states (5b and 6b).