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31.
The coordination chemistry of platinum(II) with a series of thiosemicarbazones {R(H)C2=N3‐N2(H)‐C1(=S)‐N1H2, R = 2‐hydroxyphenyl, H2stsc; pyrrole, H2ptsc; phenyl, Hbtsc} is described. Reactions of trans‐PtCl2(PPh3)2 precursor with H2stsc (or H2ptsc) in 1 : 1 molar ratio in the presence of Et3N base yielded complexes, [Pt(η3‐ O, N3, S‐stsc)(PPh3)] ( 1 ) and [Pt(η3‐ N4, N3, S‐ptsc)(PPh3)] ( 2 ), respectively. Further, trans‐PtCl2(PPh3)2 and Hbtsc in 1 : 2 (M : L) molar ratio yielded a different compound, [Pt(η2‐ N3, S‐btsc)(η1‐S‐btsc)(PPh3)] ( 3 ). Complex 1 involved deprotonation of hydrazinic (‐N2H‐) and hydroxyl (‐OH) groups, and stsc2? is coordinating via O, N3, S donor atoms, while complex 2 involved deprotonation of hydrazinic (‐N2H‐) and ‐N4H groups and ptsc2? is probably coordinating via N4, N3, S donor atoms. Reaction of PdCl2(PPh3)2 with Hbtsc‐Me {C6H5(CH3)C2=N3‐N2(H)‐C1(=S)‐N1H2} yielded a cyclometallated complex [Pd(η3‐C, N3, S‐btsc‐Me)(PPh3)] ( 4 ). These complexes have been characterized with the help of analytical data, spectroscopic techniques {IR, NMR (1H, 31P), U.V} and single crystal X‐ray crystallography ( 1 , 3 and 4 ). The effects of substituents at C2 carbon of thiosemicarbazones on their dentacy and cyclometallation are emphasized. 相似文献
32.
Abstract
Direct reductive amination of 1,3-diphenyl-1H-pyrazole-4-carbaldehyde and 3-(4-methylphenyl)-1-phenyl-1H-pyrazole-4-carbaldehyde with various substituted aromatic amines using NaBH4 in the presence of I2 as reducing agent is described. The reaction has been carried out in anhydrous methanol under neutral conditions at room temperature. The structure of newly synthesized diphenyl pyrazolylmethylanilines was established on the basis of IR, 1H, 13C NMR, and mass spectral data. All diphenyl pyrazolylmethylaniline derivatives were tested in vitro for their antifungal and antibacterial activity against different strains of fungi and bacteria. Most of the compound exhibited considerable antifungal activity but poor antibacterial activity against the test strains. 相似文献33.
Prof. Dr. Tarlok S. Lobana Poonam Kumari Gagandeep Bawa Geeta Hundal Ray J. Butcher Francisco J. Fernandez Jerry P. Jasinski James A. Golen 《无机化学与普通化学杂志》2012,638(5):804-810
Complexes of pyrrole‐2‐carbaldehyde thiosemicarbazones, [(C4H4N4)(H)C2=N3–N2(H)–C1(=S)–N1HR; R = Ph, H2L1; Me, H2L2; H, H2L3] with nickel(II) and palladium(II) are described. The reaction of nickel(II) acetate with H2L1 in methanol in 1:1 molar ratio yielded a complex of composition, [Ni(κ2‐N3,S‐HL1)2] ( 1 ). Likewise reaction of NiCl2 with H2L2 in 1:1 molar ratio in acetonitrile in the presence of triethylamine base followed by the addition of pyridine did not yield the anticipated [Ni(κ3‐N4,N3,S‐L2)(py)] complex, moreover a bis‐square‐planar complex, [Ni(κ2‐N3,S‐HL2)2] ( 2 ) was formed. However, in the presence of bipyridine (bipy), it yielded the addition product, [Ni(κ2‐N3,S‐HL2)2(κ2‐N, N‐bipy)] ( 3 ). Reaction of PdCl2(κ2‐P, P–PPh2–CH2–PPh2) with H2L3 in toluene in the presence of triethylamine has yielded a complex of stoichiometry, [Pd(κ3‐N4,N3,S–L3)(κ1‐P–PPh2–CH2–P(O)Ph2] ( 4 ). The ligands (HL1)– and (HL2)– are chelating to NiII metal atom as anions binding through N3,S‐donor atoms with pendant pyrrole groups, and (L3)2– is chelating to the PdII metal atom as dianion through N4,N3,S‐donor atoms (pyrrole is N4‐bonded). Fourth site in 4 is bonded to one P‐donor atom of PPh2–CH2–P(O)Ph2, whose pendant –PPh2 group involves auto oxidation to –P(O)PPh2 during reaction. These complexes were characterized using analytical data, IR, NMR (1H, 31P) spectroscopy and X‐ray crystallography. Complexes 1 , 2 , and 4 have square‐planar arrangement, whereas complex 3 is octahedral. 相似文献
34.
Gupta N Gupta R Chandra S Bawa SS 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(6):1175-1180
A series of new mono and binuclear copper (II) complexes [Cul]X(2)and [Cu(2)lX(2)] where 1 = L(1), L(2) and L(3) are the macrocyclic ligands. In mononuclear complexes the geometry of Cu(II) ion is distorted squareplanar and in binuclear complexes the geometry of Cu(II) is tetragonal. The synthesized complexes were characterized by spectroscopic (IR,UV-vis and ESR) techniques. Electrochemical studies of the complexes reveals that all the mononuclear Cu(II) complexes show a single quasireversible one-electron transfer reduction wave (E(pc) = -0.76 to -0.84V) and the binuclear complexes show two quasireversible one electron transfer reduction waves (E(pc)(1) = -0.86 to -1.01V, E(pc)(2) = -1.11 to -1.43V) in cathodic region. The ESR spectra of mononuclear complexes show four lines with nuclear hyperfine splittings with the observed g(11) values in the ranges 2.20-2.28, g( perpendicular) = 2.01-2.06 and A(11) = 125-273. The binuclear complexes show a broad ESR spectra with g = 2.10-2.11. The room temperature magnetic moment values for the mononuclear complexes are in the range [mu(eff) = 1.70-1.72BM] and for the binuclear complexes the range is [mu(eff) = 1.46-1.59BM]. 相似文献
35.
Pyridine-2-carbaldehyde thiosemicarbazones [C5H4N1-C(H)N2-N3H-C(S)-N4HR, R = H, L1H2; CH3, L2H2-Me; CH2CH3, L3H2-Et] with Ru(PPh3)3Cl2 have formed mononuclear RuII precursors for the generation of trinuclear complexes. The reaction of 2 mol each of L1H2, L2H2-Me, or L3H2-Et with Ru(PPh3)3Cl2 in the presence of Et3N has yielded mononuclear complexes [Ru(N3,S-L1H)2(PPh3)2] (1), [Ru(N3,S-L2H-Me)2(PPh3)2] (2), and [Ru(N3,S-L3H)2(PPh3)2] (3). The addition of 2 equiv of copperI chloride solution to complex 1 in acetonitrile has formed a novel trinuclear complex, (Ph3P)2RuII(L1)2CuII2Cl2 (4), in which the pendant amino group (-N4H2) loses one hydrogen along with the oxidation of CuI to CuII. In this complex, RuII is bonded to two P, two S, and two N3 atoms, while each CuII is coordinated to N1, N2, N4, and Cl atoms. Reaction with copper(I) bromide yielded a similar trinuclear complex, (Ph3P)2Ru(L1)2CuII2Br2 (5). From precursors 2 and 3, analogous complexes (Ph3P)2RuII(L2-Me)2CuII2Cl2 (6), (Ph3P)2RuII(L2-Me)2CuII2Br2 (7), (Ph3P)2RuII(L3-Et)2CuII2Cl2 (8), and (Ph3P)2RuII(L3-Et)2CuII2Br2 (9) have been synthesized. These complexes have been characterized using analytical, spectroscopic, and electrochemical techniques. Single-crystal X-ray crystallography has been carried out for precursor 2 and all of the trinuclear complexes, 4-9. X-band electron spin resonance and UV-vis spectra have confirmed the presence of CuII. The cyclic voltammetry studies support the RuII/RuIII redox behavior of this metal in trinuclear complexes. 相似文献
36.
A family of third-order variable-mesh methods for singularly perturbed two-point boundary-value problems of the form y=f(x,y,y),y(a)=A, y(b)=B is derived. The convergence analysis is given, and the method is shown to have third-order convergence properties. Several test examples are solved to demonstrate the efficiency of the method. 相似文献
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