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Source of materialAm ixture of CuBr (0.0435 g, 0.3 mmol) and bis(diphenylphosphino)methane (dppm, 0.1155 g, 0.3 mmol) in the presence of an excess of quinoline (1 ml) in acetonitrile (5 ml) was stirred at room temperature for 7hours, then filtered. Subsequent diffusion of diethyl ether vapor into the filtrate resulted in the formation of yellow crystals of the title compound. DiscussionThe four-electron-donor diphosphine ligand, bis(diphenylphosphino)methane, is avery efficient bridging bidentate ligand [1]. Complexes consisting of bridging diphosphine compound dppm can give aM 2 P 4 core structure with the two metal atoms held in close distance (regardless of whether ametal-metal bond is present or not) [2]. Various bi-, tri-, or tetranuclear copper(I) complexes with dppm have been already synthesized and characterized, for instance,[Cu 4(m-dppm)4(m-S)](PF6)2CH2Cl2 [4]. In the complexes with similar structures, copper atoms have the similar coordination.In the crystall structure of the title compound the bromine atom Br1 asymmetrically bridges two copper atoms. The copper atoms are triply bridged by two dppm ligands and one bromine atom, giving an eight-membered Cu 2P4C2 ring. In addition, one copper atom is terminally bound by the nitrogen atom from isoquinoline, while the other by abromine atom Br2. Both copper atoms are tetra-coordinated in aslightly distorted tetrahedral arrangement. The P-M-Pangles are not restricted by steric crowding of dppm phenyl rings. The P-Cu-Pangles in the title complex particularly are of much less linearity (120.44(2)°for P1-Cu1-P4 and 111.40(2)°for P3-Cu2-P2) than the corresponding P-Cu-Pvalues of 131.

Source of material PrO) 2 )] (0.1033 g, 0.3 mmol) was dissolved in 10 ml methylene dichloride. The solution yielded white precipitation immediately when phen (1,10-phenanthroline, 0.1189 g, 0.6 mmol) was added after the solution was stirred for 6 h at RT. Then the suspension was stirred for another 6 h. After filtration, the filtrate was allowed to stand still. Slow evaporation of the solvent yielded yellow powder solid. Recrystallization of the solid from DMF (N,N-dimethylformamide) gave yellow crystals. DiscussionLanthanide complexes have interesting photophysical properties, and the chemistry of metal phosphonates has been a research field of rapid expansion due to their potential application in the area of catalysis, ion exchange and material chemistry. Phen (phenanthroline), usually acting as a bidentate co-ligand, is mostly used as an auxiliary ligand in the mixed-ligand complexes to enhance the fluorescent properties and control the dimensionality. We are interested in lanthanoid methylenediphosphonate complexes [1]. The single-crystal X-ray diffraction study revealed that the mononuclear complex CeCl 3 (phen) 2 DMF · DMF was obtained despite the presence of tetrakis(O-isopropyl)methylenediphosphonate (figure, top). In the title complex, phen just acts as the second ligand. The IR spectrum also illustrates only phen coordinated to the central atom besides the chloride ions and DMF. This shows that the coordination ability of CH 2 [P(O)( i PrO) 2 ] 2 is weaker than that of phen. Most surprisingly, the DMF which we used as solvent is coordinated to the Ce atom through the oxygen atom. In the complex [Nd 4 (OH){(p-tert-butyltetrathiacalix[4]arene-4H)-(DMF)} 2(DMF)6(DMSO)2](NO3)3 · 3H2O [2], both DMF and DMSO solvate are also found as ligands of the rare earth atom. The cerium atom is coordinated by four nitrogen atoms from two phen ligands, one oxygen atom from DMF, and three chloride ions with the total coordination number of 8. There is also a free DMF molecule out of the coordination sphere. The average CeN bond distance of 2.699 Å is slightly shorter than the average value of 2.713 Å for the complex [Ce 2(IDA)2(C2O4) (phen) figure (figure, bottom) shows that the title compound is a supermolecular assembly formed by the p-p packing interaction of phen ligands along two perpendicular directions.

Source of materialNd(NO 3)3 ·n H 2 O( 0.1797 g, 0.4 mmol) was dissolved in 5m l pyridine. Then tetrakis(O-isopropyl)-methylenediphosphonate (L =( i PrO) 2 P(O)CH 2 P(O)( i PrO) 2 ;0 .0689 g, 0.2 mmol) which was dissolved in 5m lm ethylene dichloride was added under stiring. After three hours stiring, phen(1,10-phen-anthroline; 0.0793 g, 0.4 mmol) was added as the second ligand, the clear pink solution was stirred for another 6hours at room temperature. Pink crystals [Nd(NO 3 ) 3 (L) 2 )] were obtained by chance through slowly evaporation of the solvent in the refrigerator. DiscussionLanthanide diphosphonate complexes have been widely studied in recent years and resulted in variety of structure types for the diphosphonate, which may be coordinated simultaneously to lanthanide ions in three different modes [1]. But the diphosphonate ligands in the compounds reported with crystal structure show only the chelating mode by now. As ac onsequence, the complexes form often dinuclear dimers, polymeric chain or network structures which are directed by the choice of metal and reaction conditions. If another ligand containing aromatic ring is added as an auxiliary one, the complexes obtained enhance the fluorescent properties and control the dimensionality. We have been interested in lanthanide with methylenediphosphonate complexes [2]. By attempt to synthesize Nd complex with mixed ligands tetrakis(O-isopropyl)methylene-diphosphonate (= L) and phen in am ild condition, an unexpected compound [Nd(NO 3 ) 3 (L) 2 )] is obtained. The single crystal X-ray study shows that there are two kind of crystals mixed equally in one pot, one is [Nd(NO 3)3(L)2)], the other is made up of phen Nd 3+ and (] is a mononuclear complex. The neodymium ion is coordinated by ten oxygen atoms, four from two Lligands, the other six from three nitrate ions. The NdO 10 coordination motif is best described as a distorted bi-capped square antiprism. The average neodymiumoxygen(P) bond distances of 2.473 Å in the title compound is slightly longer than the average value of 2.438 Å reported for the complexe . The bidentate nitrate ion shows neodymium-oxygen(N) bond distances of 2.580 Å which is almost equal to the average value of 2.588 Å [4]. The ∠O7−Nd1−O8 (47.92°) in the title compound is ab it wider than the ∠O3−Nd1−O4 (48.21°), and ∠O10−Nd1− O10' (49.53°) is almost equal to ∠O1−Nd1−O1' (49.40°) [4]. The ligands are disposed in afacial arrangement with ∠N−Nd−Nbeing slightly narrower than90°, with an average of 87.25°, whilst the ∠(P)O−Nd−O(P) display anarrow angle of 74.32°. This appear to be an electrostatic rather than steric effect, with the repulsions from two negative oxygen atoms per nitrate ion dominating the increased repulsions from the bulky diphosphonate groups. There is no hydrogen bond observed in the title compound. The high Riscaused by the crystal internal factors. Because the isopropyl group from the phosphate is bounded, thermal vibration of the carbon atoms from isopropyl group is severe.

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