LI Zhi-HongGUO Wen-JingXIE Zheng-XingWANG Yong-ToWEI Qio-Hu， ②（Institute of Nnomedicine nd Nnoiosensing，College of Chemistry， Fuzhou University， Fuzhou 350108， Chin）（Stte Key Lortory of Structurl Chemistry， Fujin Institute of Reserch on the Structure of Mtter nd Grdute School of CAS， the Chinese Acdemy of Sciences， Fuzhou 350002， Chin）

Synthesis， Structure and Photophysical Properties of Heteronuclear Pt2Cu Alkynyl Complexes①

LI Zhi-HongaGUO Wen-JingaXIE Zheng-XiangaWANG Yong-TaoaWEI Qiao-Huaa， b②a（Institute of Nanomedicine and Nanobiosensing，College of Chemistry， Fuzhou University， Fuzhou 350108， China）
b（State Key Laboratory of Structural Chemistry， Fujian Institute of Research on the Structure of Matter and Graduate School of CAS， the Chinese Academy of Sciences， Fuzhou 350002， China）

Two luminescent hetero-trinuclear complexes ［Pt2Cu（μ-dpppy）2（C≡CC6H4R-4）4］（ClO4）（R = H， 1； R = CH3， 2； dpppy = 2，6-bis（diphenylphosphino）pyridine） have been synthesized and characterized by elemental analyses， ESI-MS，1H and31P｛1H｝ NMR spectroscopy， and X-ray crystallography for 2. Their photophysical properties in the solid state and in solutions at room temperature and in frozen glasses at 77 K were studied. Both complexes 1 and 2 show strong orange-red emission in the solid state at room temperature and in frozen glasses at 77 K， and weak emission in solutions.

platinum（II）， copper（I）， crystal structure， heteronuclear alkynyl complexes；

1 INTRODUCTION

Heterometallic alkynyl complexes， especially Pt（II）-M（I） （M = Cu（I）， Ag（I）） heterometallic alkynyl complexes， have attracted growing attention since the last few decades， owing to the interesting chemical reactivity， diversified structural topologies，and interesting luminescent properties suitable in the field of materials science［1-25］. It is an effective preparative methodology of Pt（II）-M（I） heterometallic alkynyl complexes by the reaction of tetraalkynylplatinate（II） complexes ［Pt（C≡CR）4］2-and M（I） （M = Cu（I）， Ag（I）） diphosphine complexes，and a series of Pt（II）-M（I） heterometallic alkynyl complexes with intriguing photophysical properties have been reported［1-25］. It is found that the structural topology of the resulting Pt（II）-M（I） alkynyl complexes depends on the metals and the type of diphosphine coligands［1-25］. Furthermore， it is now widely recognized that the luminescent properties of heterometallic alkynyl complexes depend on the structural features， the nature of metal， alkynyl substituents， and coligands［1-26］.

Recently， our group has found that the building block ［Ag2（μ-dpppy）3］2+（dpppy = 2，6-bis（diphenylphosphino）pyridine） is a good candidate for preparing heterometallic alkynyl complexes［25， 26］due to the different coordination modes of dpppy with transition metals［27-30］. These have prompted us to study on the self-assembly reaction between the tetraalkynylplatinate（II） complexes ［Pt（C≡CR）4］2-and ［Cu2（μ-dpppy）3］2+. It is envisaged that the use ofcopper（I） metal will provide an opportunity for the systematic variation of structural topology of the desired complexes， which would produce a novel luminescence.

In this contribution， we describe the syntheses and structural characterization， and their photophysical properties of hetero-trinuclear complexes ［Pt2Cu（μdpppy）2（C≡CC6H4R-4）4］（ClO4） （R = H， 1； R = CH3， 2；dpppy = 2，6-bis（diphenylphosphino）pyridine）..

2 EXPERIMENTAL

2. 1 Materials and instruments

The reactions were carried out under a dry nitrogen atmosphere using Schlenk techniques. The solvents were purified and distilled by standard procedures prior to use. The ligand 2，6-bis（diphenylphosphino）pyridyl （dpppy） was purchased from Lude fine chemical industry Co.， Ltd.， China. Phenyl-acetylene （HC≡CC6H5） and 4-methylphenylacetylene （HC≡CC6H4CH3-4） were obtained from Acros Organics. ［NBu4］2［Pt（C≡CC6H4R-4）4］ （R = H，CH3）［22-25］and ［Cu2（μ-dpppy）3］（ClO4）2［30］were prepared by the literature procedures.

Infrared spectra were recorded on a Magna750 FT-IR spectrophotometer with KBr pellets. Elemental analyses （C， H， N） were carried out on a Perkin-Elmer model 240C automatic instrument and positive ESI mass spectra （ESI-MS） were performed on the Thermo Finnigan DECAX-3000 LCQ mass spectrometer using dichloromethane-methanol or acetonitrile-methanol as mobile phase at Fujian Institute of Research on the Structure of Matter， the Chinese Academy of Sciences.1H NMR spectra with chemical shifts reported relative to tetramethylsilane and31P｛1H｝ NMR spectra with chemical shifts relative to 85% H3PO4external reference were recorded on Bruker AVANCE spectrometers. UV-vis absorption spectra in solutions and solid-states were measured on a Perkin-Elmer Lambda 950 UV-Vis spectrometer. Steady-state emission and excitation spectra in solid at room temperature or 77 K were recorded on a Perkin-Elmer LS 55 luminescence spectrometer with a red-sensitive photomultiplier type R928 and in solution on CARY Eclipse fluorescence spectrometer. Emission lifetimes were determined on an Edinburgh Analytical Instrument （FLS-902 fluorescence spectrometer） with μF900H microsecond flash lamp. The instrument response function at the excitation wavelength was decon- volved from the luminescence decay.

2. 1. 1 Synthesis of ［Pt2Cu（μ-dpppy）2（C≡CC6H5）4］（ClO4） （1）

A dichloromethane （100 mL） solution of ［NBu4］2［Pt（C≡CC6H5）4］ （390 mg， 0.36 mmol） was added dropwise to a dichloromethane solution （20 mL） of ［Cu2（μ-dpppy）3］（ClO4）2（200 mg， 0.12 mmol）. The resulting mixture was stirred for 6 h to give a yellow solution， and then concentrated under reduced pressure. The crude products were purified by column chromatograph on a silica gel （100～200 mesh） using dichloromethane-acetone （10:1 v/v） as the eluent. The products were isolated as wellshaped orange crystals by layering petroleum ether onto their concentrated dichloromethane solutions. Yield: 217 mg （65%）. Anal. Calcd. for C90H66N2Pt2CuP4ClO4: C， 58.35； H， 3.59； N， 1.51%. Found: C， 58.47； H， 3.71； N， 1.38%. ESI-MS （m/z （%））: 1752.8 （100） ［M-（ClO4）］+. IR （KBr， ν）: 2116 cm-1（w， C≡C）， 2067 cm-1（w， C≡C）， 1097 cm-1（s，ClO4）.1H NMR （400.1 MHz， CDCl3， ppm）: δ 7.66 （d， J = 6.8 Hz， 20H）， 7.43 （t， J = 7.2 Hz， 10H），7.32～7.25 （m， 16H）， 7.00 （t， J = 7.2 Hz， 4H）， 6.91 （t， J = 7.2 Hz， 8H）， 6.44 （t， J = 7.2 Hz， 8H）.31P｛1H｝NMR （202.3 MHz， CDCl3， ppm）: 21.89 （t， JPt-P= 2543 Hz， PtPPyPPt）.

2. 1. 2 Synthesis of ［Pt2Cu（μdpppy）2（C≡CC6H4-CH3-4）4］（ClO4） （2）

The same synthetic procedure as 1 was employed to prepare 2 by the reaction of ［Cu2（μdpppy）3］（ClO4）2（200 mg， 0.12 mmol） with ［NBu4］2［Pt（C≡CC6H4CH3-4）4］ （410 mg， 0.36 mmol）. Yield: 192 mg （56%）. Anal. Calcd. for C94H74N2Pt2CuP4ClO4: C， 59.15； H， 3.91； N， 1.47%. Found: C， 59.02； H； 3.95， N， 1.43%. ESI-MS ［m/z （%）］: 1808.9 （100） ［M-（ClO4）］+. IR （KBr， ν）: 2111cm-1（w， C≡C）， 2070 cm-1（w， C≡C）， 1096 cm-1（s，ClO4）.1H NMR （400.1 MHz， CDCl3， ppm）: δ 7.66 （d， J = 6.4 Hz， 20H）， 7.43 （t， J = 7.2 Hz， 10H），7.31～7.26 （m， 16H）， 6.70 （t， J = 8.0 Hz， 8H）， 6.30 （d， J = 8.0 Hz， 8H）， 2.22 （s，12H， CH3）.31P｛1H｝NMR （202.3 MHz， CDCl3， ppm）: 21.47 （t， JPt-P= 2555 Hz， PtPPyPPt）.

2. 2 Crystal structural determination

The crystal 2 coated with epoxy resin was measured on a BRUKER SMART CCD diffractometer by θ and ω scan mode at 273 K using graphite-monochromated Mo-Kα （λ = 0.71073 Å）radiation at Xiamen University. An absorption correction by SADABS was applied to the intensity data. Complex 2 crystallizes in the monoclinic system， space group P21/n with a = 16.479（3）， b = 16.655（3）， c = 16.778（3） Å， β = 111.804（2）º， V = 4275.4（12） Å3， Mr= 2078.45， Z = 2， Dc= 1.615 g/cm3， μ = 3.795 mm-1and F（000） = 2060. A total of 27673 reflections were collected in the θ range of 1.48～24.00° with 6697 unique ones （Rint= 0.0241）. The structure was solved by direct methods and the heavy atoms were located from E-map. The other non-hydrogen atoms were determined from the successive difference Fourier syntheses. All nonhydrogen atoms were refined anisotropically except those disordered oxygen atoms of the anion （ClO4-）. The bond distances of Cl（3）-O of crystal 2 were fixated as 1.40 Å using the order of dfix. The hydrogen atoms were generated geometrically and refined with isotropic thermal parameters. The structure was refined on F2by full-matrix leastsquares methods using SHELXTL-97 program package［31］. The final refinements converged at R = 0.0290， wR = 0.0792 （w = 1/［σ2（Fo2） + （0.0486P）2+ 10.56P］， where P = （Fo2+ 2Fc2）/3）， S = 1.033，（Δ/σ）max= 0.000， （Δρ）max= 1.628 and （Δρ）min= -1.385 e/Å3. The selective bond distances and bond angles of compound 2 are listed in Table 1.

Table 1. Selected Bond Distances （Å） and Bond Angles （º） of Compound 2

3 RESULTS AND DISCUSSION

3. 1 Synthesis and characterization

Compounds 1 and 2 were prepared by the reaction of ［Cu2（μ-dpppy）3］（ClO4）2with three equivalent ［NBu4］2［Pt（C≡CC6H4R-4）4］ （R = H， CH3） in dichloromethane solutions， which are closely analogous to a well established method leading to the families of heteronuclear Pt（II）-M（I） （M = Cu（I），Ag（I）） clusters［22-25］. The crude products were purified by column chromatograph on a silica gel （100～200 mesh） using dichloromethane-acetone（10:1 v/v） as the eluent. The products， isolated as well-shaped orange crystals （yield: 65% for 1 and 56% for 2） by layering petroleum ether onto their concentrated dichloromethane solutions， were satisfactorily characterized by elemental analyses， ESIMS，1H and31P｛1H｝ NMR spectroscopy.

IR spectra of compounds 1 and 2 both display two weak ν （C≡C） stretching vibrations in the ranges of 2111～2116 and 2070～2079 cm-1， respectively，because there are two different bonding modes （μ-η1（σ）， μ-η1（σ）， η2（π）） of C≡CC6H4R-4 ligand. The ESI-MS of compounds 1 and 2 showed themolecular ion fragments ［M-（ClO4）］+as the principal peaks with high abundance. The31P｛1H｝NMR spectra of compounds 1 and 2 in CDCl3or CD3CN solution both show only one set of typical P satellite peaks arising from the Pt-P coupling occurs at 21.47～21.89 ppm with JPt-Pvalue in the range of 2543～2555 Hz， indicating that all phosphorus atoms coordinated to the platinum atoms in each solution of 1 and 2 are equivalent， and each phosphorus atom is trans to the phosphorus atom， rather than trans to acetylide.

3. 2 Crystal structures

The structure of 2 was determined by X-ray crystallography， and ORTEP drawing of the cation of 2 is shown in Fig. 1. The cation of compound 2 shows a typical face-to-face arrangement with two mutually eclipsed platinum square planes bridged by two dpppy ligands to form a twelve-membered ring. Each Pt（II） center is located in an approximately square-planar environment with two alkynyl groups （C-Pt-C， 173.8（2） Å） and two bridging dpppy phosphorus atoms （P-Pt-P， 174.6（4） Å） in a trans disposition. The Pt（II）··Pt（II） separation of 5.4012（3）Å is much longer than the sum of Van der Waals radii of two Pt（II） atoms （3.5 Å）， and is also longer than that of the similar ［Pt2Ag（μdpppy）2（C≡CC6H4R-4）4］（ClO4） （Pt（II）··Pt（II），5.122（3） Å）［25］and other face-to-face dinuclear platinum（II） alkynyl complexes［1-7］， suggesting that there is no direct interaction between the two Pt（II）atoms. Interestingly， the copper（I） atom is located at the centre of the twelve-membered ring， and coordinated to one pair of symmetrical alkynyl ligands in a linear environment through π-coordination （C（11）-Cu（1）-C（11A） 180.0（2）º， C（12）-Cu（1）-C（12A） 180.0（2）º）， which is rarely found in the reported heteronuclear Pt（II）-Cu（I） complexes［1-7］. The distance of Pt（II）··Cu（I） of 2.7006（3） Å is much shorter than the sum （3.12 Å） of van der Waals radii of platinum and copper， indicating the presence of strong Pt（II）··Cu（I） bonding interactions， which are much shorter than those observed in our reported PtCu and PtCu2complexes［23］. Four acetylides in 2 adopt two different bonding modes. Two of them exhibit μ-η1:η2bonding mode， bound to the Pt（II）and Cu（I） atoms with one short （2.009（9） Å） and one longer Cu（I）-C （2.484（5） Å） distances， whereas the others are only bonded to the Pt（II） centre in η1fashion. The bond distances of Pt（II）-C fall in the range of 2.003（5）～2.015（5） Å， compared to those found in the Pt（II）-M（I） heterometallic alkynyl cluster［16-25］. The bond distances of C≡C vary from 1.195（7） to 1.198（7） Å， compared to those found in similar ［Pt2Ag（μ-dpppy）2（C≡CC6H4R-4）4］（ClO4） （R = H； R = CH3）［25］.

Fig. 1. ORTEP drawing of the cation of 2 （30% thermal ellipsoids） with hydrogen atoms and phenyl rings on the phosphorus atoms omitted for clarity

3. 3 Photophysical properties

The electronic absorption spectra of complexes 1 and 2 in dichloromethane characterized by intense high-energy absorption bands at 233 nm with a shoulder at 253～256 nm and a low-energy band at ca. 420～423 nm. The intense high-energy bands areassigned to the transitions of dpppy ligand， owing to the similar absorption energies with those of free dpppy ligand［25］. The low energy absorption in tolylacetylide derivative 2 （423 nm） is slightly red shifted in relation to that of complex 1 （420 nm）， as well as the absorption energies of the low-energy bands of complexes 1 and 2 are much lower than that of the analogue ［Pt2Ag（μdpppy）2（C≡CC6H4R-4）4］（ClO4） （R = H； R = CH3）［25］，which are similar to that observed in the related Pt（II）-M（I） acetylides［16-21， 23］. These results suggest that the low energy absorption may arise from a character of platinum-ligand to heterometal （Pt/C≡CR→Cu） character likely mixed with some intraligand contribution π→ π* （C≡CR）.

With under λex＞ 300 nm excitation， complexes 1 and 2 show strong emission in the solid state at room temperature （See Fig. 2） and in frozen glasses at 77 K， and weak emission in acetonitrile and dichloromethane solution at room temperature （Table 2）. In the solid state， complex 1 exhibits an intense red luminescence at 595 nm with the luminescence lifetime of 8.9 μs， ensuring the origin of emission from the triplet manifold. The emission is slightly blue-shifted in relation to that of the tolylacetylide derivative 2 （600 nm， τ = 6.8 μs）， which is consistent with the presence of better electron-donating ability of C≡CC6H4CH3-4 ligand. The similar blue shift from 1 to 2 is also found in solutions at room temperature and in frozen glasses at 77 K. A large blue shift of 28～45 nm occurs for complexes 1 and 2 upon cooling from 298 to 77 K. Compared to the analogue ［Pt2Ag（μ-dpppy）2（C≡CC6H4R-4）4］（ClO4）（R = H； R = CH3）［25］complexes， an obvious red-shift （ca. 100 nm） of the emission is observed in the Pt2Cu complexes 1 and 2. Based on these results， the emissive origin of the trinuclear Pt2Cu complexes is likely associated with LMMCT ［RC≡C→Pt2Cu）］ in view of the short Pt（II）-Cu（I） contacts， and likely with some intraligand contribution π→π* （C≡CR），as suggested elsewhere for the other Pt（II）-M（I） （M = Ag， Cu） acetylides［1-7， 16-25］.

Table 2. Photophysical Data for Compounds 1 and 2

Fig. 2. Normalized emission spectra of complexes 1 （black solid line） and 2 （red short dot） in the solid state at room temperature

4 CONCLUSION

In summary， we synthesized and characterized two novel luminescent hetero-trinuclear complexes ［Pt2Cu（μ-dpppy）2（C≡CC6H4R-4）4］（ClO4） （R = H， 1；R = CH3， 2； dpppy = 2，6-bis（diphenylphosphino）pyridine）. Both complexes 1 and 2 show strong orange-red emission in the solid state at room temperature and in frozen glasses at 77 K， and weak emission in solutions. Compared to the analogue Pt2Ag complexes， the emission of 1 and 2 is ca. 100 nm red-shifted， suggesting that the luminescent properties of Pt2M heterometallic alkynyl complexes mainly depend on the nature of the metal.

REFERENCES

（1） Yam， V. W. W. Molecular design of transition metal alkynyl complexes as building blocks for luminescent metal-based materials: structural and photophysical aspects. Acc. Chem. Res. 2002， 35， 555-563.

用F检验判定毒力回归方程线性关系；用LSD法进行差异显著性分析；根据试验数据组建豆蚜的生殖力表，计算种群动态参数：净增殖率R0＝ΣLXMX；平均世代周期 T＝ΣXLXMX／ΣLXMX； 内禀增长率 rm＝lnR0／T；周限增长率 λ＝exp（rm）；种群加倍时间 t＝ln2／rm。式中，X为时间间隔（d）；LX表示任意一个体在X期间的存活率；MX表示在X期间平均每雌产蚜数。

（2） Leung， S. Y. L.； Lam， W. H.； Zhu， N. Y.； Yam， V. W. W. Synthesis， structural characterization， and photophysical study of luminescent face-to-face dinuclear platinum（II） alkynyl phosphine complexes and their tetranuclear mixed-metal platinum（II）-silver（I） and -copper（I） complexes. Organometallics 2010， 29， 5558-5569.

（3） Lang， H.； Villar， A. D.； Walfort， B.； Rheinwald， G. Synthesis and reactivity of platinum（II） and copper（I） coordination polymers； the solid-state structure of ｛trans-（Ph3P）2Pt［（η2-C≡CPh）CuBr］2｝nand trans-（Ph3P）2Pt［（η2-C≡CPh）CuNO3］2. J. Organomet. Chem. 2004， 689， 1464-1471.

（4） Buschbeck， R.； Low， P. J.； Lang， H. Homoleptic transition metal acetylides. Coord. Chem. Rev. 2011， 255， 241-272.

（5） Berenguer， J. R.； Lalinde， E.； Moreno， M. T. An overview of the chemistry of homo and heteropolynuclear platinum complexes containing bridging acetylide （μ-C≡CR） ligands. Coord. Chem. Rev. 2010， 254， 832-875.

（6） Berenguer， J. R.； Fernández， J.； Gil， B.； Lalinde， E.； Sánchez， S. Rhomboidal heterometallic alkynyl based Pt2Cd2clusters: structural， photophysical，and theoretical studies. Inorg. Chem. 2010， 49， 4232-4244.

（7） Chen， Z. N.； Zhao， N.； Fan， Y.； Ni， J. Luminescent groups 10 and 11 heteropolynuclear complexes based on thiolate or alkynyl ligands. Coord. Chem. Rev. 2009， 253， 1-20.

（8） Adams， C. J.； Raithby， P. R. Novel mixed-metal-alkynyl complexes stabilized by di-imine ligands: synthesis， characterization and electrochemistry of［（tBu2bipy）Pt（C≡CR）2M（SCN）］（R = C6H4Me， SiMe3； M = Cu， Ag）. J. Organomet. Chem. 1999， 578， 178-185.

（9） Adams， C. J.； Fey， N.； Harrison， Z. A.； Sazanovich， I. V.； Towrie， M.； Weinstein， J. A. Photophysical properties of platinum（II）-acetylide complexes: the effect of a strongly electron-accepting diimine ligand on excited-state structure. Inorg. Chem. 2008， 47， 8242-8257.

（11） Fortin， D.； Clément， S.； Gagnon， K.； Bérubé， J. F.； Stewart， M. P.； Geiger， W. E.； Harvey， P. D. Conjugated organometallic polymer containing a redox-active center. Inorg. Chem. 2009， 48， 446-454.

（12） Wong， W. Y.； Lu， G. L.； Choi， K. H. Synthesis， characterization and structural studies of new heterometallic alkynyl complexes of platinum and group 11 metals with chelating bis（diphenylphosphino） ferrocene ligand. J. Organomet. Chem. 2002， 659， 107-116.

（13） Ara， I.； Berenguer， J. R.； Eguizábal， E.； Forniés， J.； Gómez， J.； Lalinde， E. Synthesis， structures and photophysics of novel luminescent platinum-copper complexes. J. Organomet. Chem. 2003， 670， 221-234.

（14） Díez， Á.； García， A.； Lalinde， E.； Moreno， M. T. A luminescent heteronuclear cluster featuring an unusual Cu6boat-shaped core assembled by two dialkynyl-cycloplatinated units. Eur. J. Inorg. Chem. 2009， 3060-3066.

（15） Pellico， D.； Gallego， M. G.； López， P. R.； Mancheňo， M. J.； Sierra， M. A.； Torres， M. R. The assembly of macrocyclic bis- and tetra-β-lactams with embedded platinum or palladium square-planar centers. Chem. Eur. J. 2009， 15， 6940-6952.

（16） Gil， B.； Forniés， J.； Gómez， J.； Lalinde， E.； Martín， A.； Moreno， M. T. Influence of solvent and weak C-H··O contacts in the self-assembled ［Pt2M4｛C≡C（3-OMe）C6H4｝8］ （M = Cu， Ag） clusters and their role in the luminescence behavior. Inorg. Chem. 2006， 45， 7788-7798.

（17） Yam， V. W. W.； Hui， C. K.； Yu， S. Y.； Zhu， N. Y. Syntheses， luminescence behavior， and assembly reaction of Tetraalkynylplatinate（II） complexes: crystal structures of ［Pt（tBu3trpy）（C≡CC5H4N）Pt（tBu3trpy）］（PF6）3and ［Pt2Ag4（C≡CC≡CC6H4CH3-4）8（THF）4］. Inorg. Chem. 2004， 43， 812-821.

（18） Forniés， J.； Lalinde， E.； Martín， A.； Moreno， M. T. Synthesis of novel platinum-silver and platinum-copper complexes with bridging alkynyl ligands. J. Organomet. Chem. 1995， 490， 179-188.

（19） Charmant， J. P. H.； Forniés， J.； Gómez， J.； Lalinde， E.； Merino， R. I.； Moreno， M. T. Orpen， A. G. Unprecedented Pt-Pt bonded trimer｛［Pt2Cu4（C≡CPh）8］｝3showing unusual near-infrared luminescence. Organometallics 1999， 18， 3353-3358.

（20） Benito， J.； Berenguer， J. R.； Forniés， J.； Gil， B.； Gómez， J.； Lalinde， E. Synthesis， characterization and luminescence properties of homoleptic platinum（II） acetylide complexes. Dalton Trans. 2003， 4331-4339.

（21） Yam， V. W. W.； Yu， K. L.； Cheung， K. K. Luminescence and aggregation studies of hexanuclear platinum-copper acetylide complexes. Crystal structure of the luminescent metal-metal bonded dimer ［Pt2Cu4（C≡CPh）8］2. J. Chem. Soc. Dalton. Trans. 1999， 2913-2915.

（22） Wei， Q. H.； Yin， G. Q.； Ma， Z.； Shi， L. X.； Chen， Z. N. Luminescent heterohexanuclear complexes with platinum alkynyl and silver diphosphine as components. Chem. Commun. 2003， 2188-2189.

（23） Yin， G. Q.； Wei， Q. H.； Zhang， L. Y.； Chen， Z. N. Luminescent PtII-MI（M = Cu， Ag， Au） heteronuclear alkynyl complexes prepared by reaction of ［Pt（C≡CR）4］2-with ［M2（dppm）2］2+（dppm = Bis（diphenylphosphino）methane）. Organometallics 2006， 25， 580-587.

（24） Wei， Q. H.； Han， L. J.； Jiang， Y.； Lin， X. X.； Duan， Y. N.； Chen， G. N. Electrochemiluminescence properties of ［Pt2Ag4（C≡CC6H4R）8］n（R = CH3， n = 1；R = H， n = 1 and 2） with amine （TPrA and DBAE） as the coreactant and determination of Sudan I. Inorg. Chem. 2012， 51， 11117-11125.

（25） Lin， X. X.； Li， Z. H.； Huang， X. Y.； Jiang， Y.； Wei， Q. H.； Chen， G. N. Pt2Ag acetylide-doped silica nanoparticles: enabling luminescence of Pt2Ag complexes in water and sensors for highly sensitive detection of cyanide anions. Dalton Trans. 2014， 43， 8861-8867.

（26） Jiang， Y.； Wang， Y. T.； Ma， Z. G.； Li， Z. H.； Wei， Q. H.； Chen， G. N. New luminescent Ag2Au2heteronuclear alkynyl-phosphine complexes and recognition of homocysteine and cysteine. Organometallics 2013， 32， 4919-4926.

（27） Song， H. B.； Zhang， Z. Z.； Hui， Z.； Che， C. M.； Mak， T. C. W. Linear heterotrinuclear complexes derived from an alkyl Platinum（II） twelve-membered macrocycle. Inorg. Chem. 2002， 41， 3146-3154.

（28） Wood， F. E.； Hvoslef， J.； Hope， H.； Balch， A. L. 2，6-Bis（diphenylphosphino） pyridine as a bridging ligand in planar complexes of platinum（II） and palladium（II）. Inorg. Chem. 1984， 23， 4309-4315.

（29） Kuang， S. M.； Zhang， L. M.； Zhang， Z. Z.； Wu， B. M.； Mak， T. C. W. Synthesis and structural characterization of binuclear silver（I） complexes bridged by three polydentate phosphine ligands. Inorg. Chim. Acta 1999， 284， 278-283.

（30） Field， J. S.； Haines， R. J.； Warwick， B. Synthesis and crystal structures of ［Cu2｛μ-（Ph2P）2py｝3］［PF6］2［（Ph2P）2py = 2， 6-bis（diphenylphosphino） pyridine，bipy = 2，2΄-bipyridine］. Polyhedron 1996， 15， 3741-3748.

（31） Sheldrick， G. M. SHELXL-97， Program for the Refinement of Crystal Structures. University of Göttingen， Germany 1997.

Received 9 December 2014， accepted 17 March 2015 （CCDC 1036008 for 2）

① Supported by NSF of Fujian Province （No. 2014J01046）， Key Science Project （type A） of the Fujian Provincial Department of Education，China （No. JA12021）， and the NSF for Fostering Talents in Basic Research of China （No. J1103303）

② Corresponding author. E-mail: qhw76@fzu.edu.cn

10.14102/j.cnki.0254-5861.2011-0599