Lewis-Base Adducts of Group-11 Metal(I) Compounds. XXXI. Reaction of 2,6-Bis[1-phenyl-1-(pyridin-2-Yl)ethyl]pyridine (L), and Copper(I) Halides in Acetonitrile: Structural Characterization of Salts of the [(MeCN)Cu(meso-L)]+ Cation

1987 ◽  
Vol 40 (11) ◽  
pp. 1881 ◽  
Author(s):  
AJ Canty ◽  
LM Engelhardt ◽  
PC Healy ◽  
JD Kildea ◽  
NJ Minchin ◽  
...  

Reaction of 2,6-bis[l-phenyl-1-(pyridin-2-yl)ethyl]pyridine, L, with copper(1) chloride, bromide, and iodide in acetonitrile solution has been shown to yield salts, structurally characterized by single-crystal X-ray diffraction methods as [( MeCN ) CuL ]+ [ ClCuCl ]-, (1), [( MeCN ) CuL ]+2 [XCuX2CuX]2-, X = Br (2), I (3) (both isomorphous ), all as yellow needles, and a form of (3), orange blocks, as the hemiacetonitrile solvate, (4), [( MeCN ) CuL ]+2 [IcuI2Cul]2-. MeCN . The same cation is common to all four species, containing four-coordinate copper(r), with L as meso -tridentate ligand; in (4), the most precisely defined example, Cu-N( MeCN ) is 1.919(5) �, the shortest copper(1) acetonitrile distance known, while Cu-N(L) are 2.065(5)-2.073(5) �. The reason for non-formation of species of the type [ LCuX ] appears to lie in the tridentate ligand conformation which permits coordination of acetonitrile but not larger halide species.

1989 ◽  
Vol 42 (6) ◽  
pp. 907 ◽  
Author(s):  
LM Engelhardt ◽  
PC Healy ◽  
JD Kildea ◽  
AH White

The mononuclear adducts chloro - and bromo-pyridinebis (triphenylphosphine)silver have been synthesized and structurally characterized by single-crystal X-ray diffraction methods. The two complexes are isomorphous, monoclinic, space group P21 or P21/m, a ≈ 9.8, b ≈ 20.0, c ≈ 9.1 � , β ≈ 97.5�, Z 2; in space group P21/m, they were refined to residuals of 0.038, 0.036 for 2392, 2157 'observed' reflections respectively. No comparable iodide adduct has been isolated. In both structures the silver atom is four-coordinate; Ag-Cl,Br are 2.511(2), 2.629(1) �; Ag-P, 2.472(1), 2.476(1) �, and Ag-N, 2.585(5), 2.570(5) � respectively, the Ag-N distance being longer than Ag-P, indicating very weak coordination of the pyridine.


1989 ◽  
Vol 42 (6) ◽  
pp. 895 ◽  
Author(s):  
LM Engelhardt ◽  
PC Healy ◽  
JD Kildea ◽  
AH White

Complexes [ XCu ( py )(PPh3)2], X = Cl, Br, I, py = pyridine, have been synthesized and characterized by single-crystal X-ray structure determination. Chloride and iodide derivatives have similar cells [ isomorphous (?) but not isostructural ], triclinic, pi, a = 19.5 A, b = 10.5, c = 9.6 � , α ≈ 66, β ≈ 86, γ ≈ 83�, Z = 2; the bromide is monoclinic, Cc, a 13.568(9), b 15.760(12), c 16.545(8) � , β 95.65(5)�, Z = 4. Cl, Br, I structures were refined to residuals of 0.042, 0.055, 0.039 for 4288, 2241, 4808 'observed' reflections. In all cases, the copper atom is four-coordinate; for such an array, Cu-X lengths are unusually short [2.318(2), 2.459(2), 2.636(1) � (Cl, Br, I) and Cu-N unusually long (2.14(1) � ], while (Cu-P) increase from 2.264 to 2.288 � across the series. The dominant aspect of the complexes is thus that of XCu (PPh3)2 solvated by pyridine.


1989 ◽  
Vol 42 (6) ◽  
pp. 913 ◽  
Author(s):  
LM Engelhardt ◽  
PC Healy ◽  
JD Kildea ◽  
AH White

Mixed base pyridine (py)/triphenylphosphine adducts of the copper(1) halides, CuX, have been synthesized for 1 : 1 : 1 stoichiometry for X = chloride and iodide; single-crystal X-ray structure determinations of these show them to be isomorphous and isostructural with that of the bromide recorded elsewhere, being �,�′- dihalo-bridged dimers , [(PPh3)( py )CuX2Cu( py )(PPh3)], monoclinic, C2/c, a ≈ 26.2, b ≈ 14.3, c ≈ 11 .2 � , β ≈ 95, Z = 4 dimers. The bromide has been isolated as a new monoclinic C 2/m polymorph, a 11 .279(8), b 14.268(6), c 13.858(4) �, β 109.33(6)�, Z=4 dimers, and details of its structure are also recorded. The structures of their pyridine-4-carbonitrile (pycn) analogues have also been determined and found to be also binuclear, with no cyano-copper interactions; these also are an isomorphous, isostructural series, monoclinic P21/n, a ≈ 15.4, b ≈ 8.1, c ≈ 17.9 � , β ≈ 101 �, Z = 2 dimers. In each series of dimers, one half of the dimer is crystallographically independent, the generators of the other half being twofold rotor (C2/c phase), mirror (C2/m phase) and inversion centre (P21/n phase) respectively.


2015 ◽  
Vol 70 (3) ◽  
pp. 165-169 ◽  
Author(s):  
Gao-Feng Wang

AbstractThe synthesis of two new copper(II) complexes with benzimidazole type ligands, Cu(tta)2(L1)2 (1) and Cu(tta)2(L1) (2) (where L1 is 3-(4-(1H-benzo[d]imidazol-1-yl)-4-methoxy phenyl)-1-phenylprop-2-en-1-one; tta is 2-thenoyltrifluoroacetonate), are reported. Their structures have been characterized by infrared spectroscopy, elemental analyses and single-crystal X-ray diffraction. The copper(II) ion of 1 is in a distorted octahedral environment, while that of 2 is in a distorted square-pyramidal environment. In both cases, the donor atoms are provided by oxygen atoms of the tta ligands and nitrogen atoms of the L1 ligands.


1988 ◽  
Vol 41 (3) ◽  
pp. 335 ◽  
Author(s):  
JC Dyason ◽  
LM Engelhardt ◽  
PC Healy ◽  
JD Kildea ◽  
AH White

Single-crystal X-ray structure determinations are recorded for two unusual trigonal planar XCuL2 species, X = halogen, L = monodentate N- base. For iodobis (2-methylquinoline)copper(I) (1) crystals are orthorhombic, P212121, a 15.079(7), b 12.592(7), c 9.585(4)Ǻ, Z 4. R was 0.028 for 1285 independent 'observed' reflections; the copper(I) environment is trigonal planar [I-Cu, 2.533(2); Cu-N, 2.034(6), 2.0l5(7)Ǻ; I-Cu-N are 119.1(2), 120.4(2) and N-Cu-N, 120.4(2)°]. For the mixed base complex bromo (3,5-dimethylpyridine)(2,4,6-trimethylpyridine )copper(I) (2), crystals are triclinic, pī , a 13.643(5), b 8.434(5), c 8.163(4)Ǻ, α 59.65(4), β 79.76(4), γ 89.68(4)°, Z 2; R was 0.046 for 1551 'observed' reflections. Br-Cu is 2.418(2); Cu-N, 1.971(5), 1.963(6)Ǻ; Br-Cu-N are 113.5(2), 110.0(2) and N-Cu-N, 136.4(3)°.


2009 ◽  
Vol 62 (9) ◽  
pp. 983 ◽  
Author(s):  
Han Vinh Huynh ◽  
Hui Xian Seow

Dicarbene complexes [Pd(OAc)2(diNHC)] (2), [Pd(O2CCF3)2(diNHC)] (3), and [Pd(CNCH3)2(diNHC)](SO3CF3)2 (4) bearing labile acetato, fluoroacetato, and acetonitrile co-ligands have been synthesized via metathesis reaction of the respective precursor [PdBr2(diNHC)] (1) with Ag-salts. All complexes are stable towards air and moisture and have been fully characterized by spectroscopic and spectrometric methods. Notably and in comparison to diphosphine analogues, they resist ligand disproportionation in solution. Their molecular structures have also been determined by single crystal X-ray diffraction. A preliminary catalytic study showed low activity in the hydroamination reaction, but revealed an interesting co-ligand influence.


1989 ◽  
Vol 42 (2) ◽  
pp. 335 ◽  
Author(s):  
LM Engelhardt ◽  
JM Patrick ◽  
AH White

The isolation and single-crystal X-ray structure determination of the title compound, [(phen)2Pb(NCS)(O2NO)] is described; crystals are triclinic, P1, a 15.554(7), b 9-670(4), c 8.429(3) α 72.53(3), β 81.90(3), γ 72.88(3)� Z = 2, yielding R 0.052 for 3405 independent 'observed' reflections. The lead atom is seven-coordinate [Pb-N 2.49(1)-2.60(1) (phen), 2.89(1) (NCS); Pb-O 2.75(1), 2.89(1) �] with a large vacancy in the coordination sphere, possibly indicative of a stereochemically active lone pair.


1997 ◽  
Vol 50 (6) ◽  
pp. 587 ◽  
Author(s):  
Effendy ◽  
John D. Kildea ◽  
Allan H. White

The syntheses and room-temperature single-crystal X-ray structural characterization of 1 : 3 adducts formed between silver(I) (pseudo-) halides, AgX, and triphenylstibine, SbPh3, are described for X = Cl, I, SCN, NCS, CN, NO3 (1)-(6). The chloride, as its methanol solvate (1a), is isomorphous with the arsine analogue: triclinic, P-1, a 13·373(4), b 14·48(6), c 14·702(3) Å, α 83·49(3), β 87·76(2), γ 76·45(3)°; Z = 2, conventional R on F being 0·046 for No 5514 independent ‘observed’ reflections (I > 3σ(I )). A new form (1b) of the chloride has also been authenticated: monoclinic, P 21/c, a 12·832(2), b 54·24(1), c 18·519(8) Å, β 129·68(3)°; Z = 8 (R 0·065 for No 5672). No bromide has been obtained; the iodide (2) is described as monoclinic, P 21/n, a 19·611(4), b 14·473(6), c 17·74(1) Å, β 98·28(3)°; Z = 4 (R 0·036 for No 6769). The thiocyanate crystallizes from acetonitrile or pyridine as an S-bonded form (3) isomorphous with the arsine analogue: monoclinic, P 21/n, a 19·143(7), b 14·288(5), c 18·694(6) Å, β 98·81(2)°; Z = 4 (R 0·037 for No 4482). From 2-methylpyridine, remarkably, a solvate is obtained in which the thiocyanate is N-bonded (4): triclinic, P-1, a 27·261(5), b 14·767(3), c 13·319(1) Å, α 91·53(1), β 101·58(1), γ 92·29(2)°; Z = 4 (R 0·045 for No 6900). The cyanide is also monoclinic, P 21/n, a 19·442(7), b 14·267(3), c 17·741(6) Å, β 97·63(3)°, z = 4; R 0·057 for No 2487. The unsolvated 1 : 3 nitrate complex (6a) is monoclinic, P 21/n, a 19·602(5), b 14·455(1), c 17·727(2) Å, β 97·19(2)°, Z = 4; R was 0·034 for No 6522. The complex is isomorphous with the arsenic and phosphorus analogues, being mononuclear [(Ph3Sb)3Ag(O2NO)]. The ethanol solvate (6b) is triclinic, P-1, a 13·352(5), b 14·548(9), c 14·701(4) Å, α 81·64(4), β 84·45(3), γ 75·32(4)°, Z = 2; R was 0·058 for No 4702. Ag-Sb range between 2·6980(8) and 2·843(3) Å in the precise determinations; Ag-X are 2·481(4) and 2·52(1) Å (the two chlorides), 2·757(1) (I), 2·533(3) (SCN), 2·21(1) (NCS), 2· 09(3) (CN), 2·377(7) Å (unidentate ONO2)


2019 ◽  
Vol 16 (33) ◽  
pp. 516-523
Author(s):  
G. E. DELGADO ◽  
L. M. BELANDRIA ◽  
M. GUILLEN ◽  
A.. J. MORA ◽  
L. E. SEIJAS

2-amino-2-oxoacetic acid, carbamoyl formic acid, or oxamic acid is an active pharmaceutical ingredient (API) of great importance mainly because is an inhibitor of lactic dehydrogenase (LDH). It acts as an inhibitor to the metabolic pathways of the tumor cells and exhibited significant anticancer activity against nasopharyngeal carcinoma (NPC) cells in vitro and can be considered as a potential drug for the treatment of type 2 diabetes. Also, this compound could be used as a building block in the design of supramolecular architectures based on hydrogen bonds through the complimentary hydrogen-bond functionalities of the carbonyl and amide functional groups present. Single-crystal X-ray diffraction is the most powerful technique for crystal structure determination of small molecules. However, for several materials, including oxamic acid, it could be complicated to grow single crystals of suitable size and quality that make them appropriated to structure analysis. For this reason, the structural study was conducted with powder X-ray diffraction which is a process significantly more challenging than structure determination from single-crystal data. Oxamic acid has been characterized by FT-IR and NMR spectroscopic techniques, thermal TGA-DSC analysis, semi-empirical PM7 calculations, and X-ray powder diffraction. The title compound crystallizes in the monoclinic system with space group Cc, Z=4, and unit cell parameters a= 9.4994(4) Å, b= 5.4380(2) Å, c= 6.8636(3) Å, b= 107.149(2)°, V= 338.79(2) Å3. The molecule has a trans conformation. The molecular structure and crystal packing are stabilized mainly by intra- and intermolecular O--H···O and N--H···O hydrogen bonds. The structural characterization of this type of API compound is important to understand its mechanisms of action due to its considerable biological effects. In particular, for oxamic acid, this structural study would allow subsequent examination of its medicinal properties as an antitumor and antidiabetic agent.


1996 ◽  
Vol 49 (12) ◽  
pp. 1273 ◽  
Author(s):  
AL Maclean ◽  
GJ Foran ◽  
BJ Kennedy ◽  
P Turner ◽  
TW Hambley

The structure of 5,10,15,20-tetraphenylporphinatonickel(II) ([Ni( tpp )]) has been studied by both X-ray diffraction (powder and single-crystal methods) and EXAFS. The bond lengths obtained from analysis of the EXAFS agree, within standard deviations, with those obtained from the X-ray diffraction studies. The Ni-N bond length of 1.93(1) Ǻ agrees especially well with the value of 1.931(2) Ǻ obtained from the single-crystal analysis. The powder X-ray diffraction pattern, collected by using synchrotron radiation, is presented.


Sign in / Sign up

Export Citation Format

Share Document