New Cyclometalated Platinum(Ⅱ) Complexes: Synthesis,X-Ray Structure and Electronic Spectra

doi:10.7517/j.issn.1674-0475.2004.05.370

Imaging Science and Photochemistry ›› 2004, Vol. 22 ›› Issue (5): 370-377.DOI: 10.7517/j.issn.1674-0475.2004.05.370

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New Cyclometalated Platinum(Ⅱ) Complexes: Synthesis,X-Ray Structure and Electronic Spectra

CAO Qian-yong¹, FU Wen-fu^1,2, JIA Lin-fang¹, YU Ming-ming¹

1. Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100101, P. R. China;
2. College of Chemistry and Chemical Engineering, Yunnan Normal University, Kunming 650092, Yunnan, P. R. China

Received:2004-06-25 Revised:2004-07-01 Online:2004-09-23 Published:2004-09-23

Abstract

Abstract: A new cyclometalated ligand 4-methoxycarbonyl-6-(4-methylphenyl)-2,2’-bipyridine (HL) and its mono- and binuclear platinum (Ⅱ) complexes (ClO₄) (1) and (ClO₄)₂ (2) (dppm=bis (diphenylphosphino)methane) were synthesized and characterized.In complex 2,the platinum (Ⅱ) center adopts distorted square planar coordination geometry and two platinum (Ⅱ) centers are bridged through biphosphine ligand dppm,and metal-metal interaction exists with Pt-Pt distance 0.3375 nm.Both complexes have low-lying absorption spectra with shoulder peak at ～450 nm which are assigned to metal to ligand charge-transfer transition (MLCT).Both complexes display strong luminescence spectra in solution or solid state.For complex 1,the low energy emission spectra of 620 nm indicates an intermolecular π-π interaction between two ligands in solid state,and in solid or fluid state metal-metal to ligand-charge-transfer (MMLCT) triplet state emissions were observed for complex 2.

Key words: cyclometallated ligand, platinum (Ⅱ) complexes, X-Ray structure, luminescence spectra

CLC Number:

CAO Qian-yong, FU Wen-fu, JIA Lin-fang, YU Ming-ming. New Cyclometalated Platinum(Ⅱ) Complexes: Synthesis,X-Ray Structure and Electronic Spectra[J]. Imaging Science and Photochemistry, 2004, 22(5): 370-377.

References

[1] Cheung T C,Cheung K K,Peng S M,Che C M.Photoluminesecent cyclometallated diplatinum(Ⅱ ,Ⅱ)complexes:photophysieal properties and crystal structures of [PtL(PPh₃)]ClO₄ and [Pt₂L₂(μ-dppm)](ClO₄)₂(HL= 6-phenyl-2,2’-bipyridine,dppm = Ph₂PCH₂PPh₂) [J].J.Chem.Soc.,Dalton Trans.,1996,1645-1651.
[2] Lai S W,Chan M C W,Cheung T C,Peng S M,Che C M.Probing d⁸-d⁸ interactions in luminescent mono- and binuclear cyclometalated platinum(Ⅱ)complexes of 6-phenyl-2,2’-bipyridines[J].Inorg.Chem.,1999,38,404-405.
[3] Lu W,Zhu N Y,Che C M.Tethered trinuclear cyclometalated platinum(Ⅱ])complexes:from crystal engineering to tunable emission energy[J].Chem.Commun.,2002,900-901.
[4] Lu W,Mi B X,Chan M C W,Hui Z,Che C M,Zhu N,Lee S T.Light-emitting tridentate cyclometalated platinum(Ⅱ)complexes containing σ-alkynyl auxiliaries: tuning of photo- and electrophosphorescence[J].J.Am.Chem.Soc.,2004,126,4958-4971.
[5] Liu H Q,Cheung T C,Che C M.Cyclometallated platinum(Ⅱ)complexes as luminescent switches for calf-thymus DNA[J].Chem.Commun.,1996,1039-1040.
[6] Wong L H W,Chan M C W,Che C M.Modular cyclometallated platinum(Ⅱ)complexes as luminescent molecular sensors for pH and hydrophobic binding regions[J].Chem.Eur.J.,1999,5,2845-2852.
[7] Che C M,Zhang J L,Lin L R.PEG-linked luminescent platinum(Ⅱ)complexes as aqueous polymeric molecular light switch for protein binding reaction[J].Chem.Commun.,2002,2556-2557.
[8] Wu L Z,Cheung T C,Che C M,Cheugn K K,Lam M H W.Dinuclear cyclometallated platinum(Ⅱ)complex as a sensitive luminescent probe for SDS micelles[J].Chem.Commun.,1998,1127-1128.
[9] Che C M,Fu W F,Lai S W,Hou U J,Liu Y L.Solvatochromic response imposed by environment changes in matrix/chromophore entities:luminescent cyclometallated platinum(Ⅱ)complex in Nafion and silica materials [J].Chem.Commun.,2003,118-119.
[10] Perrin D D,Armarego W L F,Perrin D R.Purification of Laboratory Chemicals [M].2nd ed.Oxford: Pergamon Press,1980.
[11] Krohnke F,Gross K F.Beispiele zur king-reaction[J].Chem.Ber.,1959,92,22-35.
[12] Higashi T.ABSCOR,Empirical Absorption Correction based on Fourier Series Approximation [M].Tokyo: Rigaku Corporation,1995.
[13] Sheldrick G M.SHELXS 97,Program for the Solution of Crystal Structure[M].University of Gottingen,1997.
[14] Sheldrick G M.SHELXL 97,Program for the Refinement of Crystal Structure [M].University of Gottingen,1997.
[15] Krohnke F.The specific synthesis of pyridines and oligopyridines[J].Synthesis,1976,1-24.
[16] Constable E C,Henney R P G,Leese T A,Tocher D A.Cyclopalladated and cycloplatinated complexes of 6-phenyl-2,2’-bipyridine: platinum-platinum interactions in the solid state[J].J.Chem.Soc.,Chem.Commun.,1990,513-514.

New Cyclometalated Platinum(Ⅱ) Complexes: Synthesis,X-Ray Structure and Electronic Spectra

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