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1.
Seed protein extracts from 477 Japanese soybean cultivars were analyzed by polyaery lamide gel electrophoresis to determine the distribution of the alleles of the Ti (Ti a,Ti b,Ti c) and Sp1 (Sp 1 a,Sp 1 b loci with respect to maturity group and district of adaptation of each cultivar. About 60 percent of the soybean cultivars had theTi a allele. The frequency of theTi b allele was found to be highest in the southeast district and lowest in the northeast district. TheTi c allele discovered in 6 cultivars was traced to two possible sources adapted in the Tohoku District. TheSp l a, allele was found in 26 cultivars ranging from Maturity Group II through VIII. The summer season type cultivars adapted to the Kyushu District having the genotypeTi b Spl b probably played a major role in the peculiar accumulation of theTi ub allele and the decrease of theSp l a allele in the Japanese soybean cultivar population. 相似文献
2.
Rafael Omar Saavedra Díaz Ronan Le Lagadec Alexander D. Ryabov 《Journal of biological inorganic chemistry》2013,18(5):547-555
Cyclometalated RuII derivatives of 2-phenylpyridine (Hphpy) [Ru(phpy)(bpy)2]Cl (1a) and [Ru(phpy)(phen)2]Cl (1b) (bpy is 2,2′-bipyridine, phen is 1,10-phenanthroline) behave as noncompetitive inhibitors of glucose oxidase from Aspergillus niger in the enzyme-catalyzed oxidation of d-glucose by O2 into the corresponding lactone at pH 5.0 and 25 °C. The enzymatic activity has been measured by monitoring the O2 consumption. The inhibition constants K i are 0.036 and 0.017 M for 1a and 1b, respectively, indicating that 1b inhibits the enzymatic activity more efficiently than 1a. The well-known coordination compound [Ru(bpy)3]Cl2 (2) behaves, in contrast, as a competitive inhibitor, with K i = 0.018 M under the same conditions. The monophasic consumption of O2 in the case of 1a, 1b, and 2 is replaced by a distinct two-phase kinetics in the presence of the cyclometalated RuIII compound [Ru(phpy)(bpy)2]Cl2 (3), which was obtained from 1a in the presence of a large excess of H2O2 and the iron TAML activator. Interestingly, the rates of the first and the second phases are influenced by 3 in a different way. The rate of the first phase is noticeably higher in the presence of RuIII, although the dependence is nonmonotonic and maximal acceleration is observed at the lowest loadings of 3. The rate of the second phase decreases monotonically on increasing the concentration of the ruthenium complex in solution. The nonmonotonic action of 3 was confirmed by using the doubly cyclometalated RuIII derivative [Ru(phpy)2(bpy)]Cl. The diverse rate variations induced by 3 accounted for acceleration by RuIII of the O2 reduction by the reduced form of glucose oxidase during the first phase, which ceases after the enzymatic reduction of RuIII to the RuII species, the latter behaving similarly to 1a as the inhibitor of the enzyme. 相似文献
3.
Akio Yamazaki Vladimir A. Bondarenko Isao Matsuura Masahiro Tatsumi Sadamu Kurono Naoka Komori Hiroyuki Matsumoto Fumio Hayashi Russell K. Yamazaki Jiro Usukura 《Molecular and cellular biochemistry》2010,339(1-2):215-233
Cyclic GMP phosphodiesterase (PDE) in bovine rod photoreceptor outer segments (OS) comprises a catalytic subunit complex (Pαβ) and two inhibitory subunits (Pγ) and is regulated by the α subunit of transducin (Tα). Here, we show an overall mechanism for PDE regulation by identifying Pγ complexes in OS homogenates prepared with an isotonic buffer. Before Tα activation, three Pγ complexes exist in the soluble fraction. Complex a, a minor complex, contains Pαβ, Tα, and a protein named Pδ. Complex b, Pαβγγ b , has a PDE activity similar to that of membranous Pαβγγ, Pαβγγ M , and its level, although its large portion is Pδ-free, is estimated to be 20–30% of the total Pαβγγ. Complex c, (Pγ·GDP-Tα) 2 c , appears to be a dimer of Pγ·GDP-Tα. Upon Tα activation, (1) complex a stays unchanged, (2) Pαβγγ b binds to membranes, (3) the level of (Pγ·GDP-Tα) 2 c is reduced as its GTP-form is produced, (4) complex d, Pγ·GTP-Tα d , is formed on membranes and its substantial amount is released to the soluble fraction, and (5) membranous Pαβγγ, Pαβγγ M and/or Pαβγγ b , becomes Pγ-depleted. These observations indicate that Pγ as a complex with GTP-Tα dissociates from Pαβγγ on membranes and is released to the soluble fraction and that Pγ-depleted PDE is the GTP-Tα-activated PDE. After GTP hydrolysis, both (Pγ·GDP-Tα) 2 c and Pγ·GDP-Tα d , without liberating Pγ, deactivate Pγ-depleted PDE. The preferential order to be used for the deactivation is membranous Pγ·GDP-Tα d , solubilized Pγ·GDP-Tα d and (Pγ·GDP-Tα) 2 c . Release of Pγ·GTP-Tα complexes to the soluble fraction is relevant to light adaptation. 相似文献
4.
The reaction of [VCl3(PMe2Ph)3] with HSS′S′SH (where the HS are thiophenolate and the S′ thioether functions, respectively), H2–1, yields [VCl(μ-SS′S′S)]2 (3) with one of the thiolate groups of each of the two ligands in the bridging mode. Reaction of Na2–1 with [VOCl2(thf)2] leads to a polymeric product of composition [VO(SS′S′S)]x (4). The products obtained from the reaction between [VOCl2(thf)2] and NaSNNSNa, Na2–2, (S is thiophenolate, N the amine function) depend on subtle changes in the diamine backbone of this ligand: If the amine functions are linked by -CH2CH2– (2a), the tetranuclear VIV complex [V(SNNS)μ-O]4 (5) is formed alongside the VIII complex [VCl(SNNS)]. If the backbone is -CH(Me)CH(Me)- (2b), [VO(SNNS)] (7) and the dinuclear, asymmetrically oxo-bridged VIV complex [{(SNN – S)(thf)V}μ-O{V(SNN – S)}] (8) are obtained. In 8, one amine of each of the two ligands is deprotonated to the amide group. In either case, the complexation is accompanied by oxidation of the thiolates to disulfides, leading to the generation of teraazatetrathio-cycloeicosanes (6a/b). Compounds 5 and 8·2THF have been structurally characterized by X-ray analyses. The connectivities have further been established for 3·2CH2Cl2 and for 6b, which exhibits the same conformation as formally characterized 6a. The cluster compound 5 is stabilized by an extended intramolecular N-H...O and N-H...S) hydrogen-bonding network. In 7·2THF, one of the THFs of crystallization is hydrogen-bonded to the NH of the penta-coordinated {VO(SNN – S)} moiety; further, there is an intramolecular hydrogen bond between one of the thiolates of this tetragonal-pyramidal half of the molecule and the NH of the octahedral {VO(SNN – S)thf} half. The generation of the ligand 2b from its precursor compound, the zinc complex [Zn(SNNS)] (9) leads to the structural characterization of 9·CH3OH with a large SZnS bite angle and a strong hydrogen bond between the methanolic OH and one of the thiolate sulfurs. The relevance of these compounds in biological systems is discussed. 相似文献
5.
A series of new ruthenium(II) carbonyl chloride complexes with pyridine-functionalised N-heterocyclic carbenes [Ru(Py-NHC)(CO)2Cl2], [Py-NHC = 3-methyl-1-(2-pyridyl)imidazol-2-ylidene, 1 (1a and 1b); 3-methyl-1-(2-picoyl)imidazol-2-ylidene, 2 (2a and 2b); 3-methyl-1-(2-pyridyl)benzimidazolin-2-ylidene, 3 (3b); 3-methyl-1-(2-picoyl)benzimidazolin-2-ylidene, 4 (4a and 4b); 1-methyl-4-(2-pyridyl)-1,2,4-triazoline-5-ylidene, 5 (5a and 5b)] have been prepared by transmetallation from the corresponding silver carbene complexes and characterized by NMR, IR spectroscopy and elemental analysis. In these complexes with bidentate Py-NHC ligands, one CO ligand is trans to the Py ligand. In 1a, 2a, 4a, and 5a, the NHC ligand is trans to the other CO ligand, thus leaving the two Cl− ligands trans to each other. In 1b, 2b, 3b, 4b, and 5b, the NHC ligands are trans to one Cl− ligand, and the two Cl− ligands are cis to each other. The structures for 1b, 2b, 3b and 4b have been determined by single-crystal X-ray diffraction. These complexes are efficient catalysts in the transfer hydrogenation of acetophenone and their catalytic activities are found to be influenced by electronic effect of the N-heterocyclic carbene ligands. 相似文献
6.
Amit Majumdar 《Inorganica chimica acta》2009,362(10):3493-361
Two hitherto unknown mixed-ligand tris chelated complexes containing 2-aminothiophenolate, [Et4N]2[MIV(NH-(C6H4)-S)(mnt)2] (M = Mo, 1a; W, 2a) and two mixed-ligand tris chelate complex containing N,N-diethyldithiocarbamate, [Et4N]2[MIV(Et2NS2)(mnt)2] (M = Mo, 1b; W, 2b) have been synthesized and characterized structurally. Although these complexes are supposed to be quite similar to the well-known symmetric tris chelate complexes of maleonitriledithiolate (mnt), [Et4N]2[MIV(mnt)3] (M = Mo, 1c; W, 2c), but display both trigonal prismatic and distorted trigonal prismatic geometry in their crystal structure indicating the possibility of an equilibrium between these two structural possibilities in solution. Unlike extreme stability of 1b, 2b, 1c and 2c, both 1a and 2a are highly unstable in solution. In contrast to one reversible reduction in case of 1b and 2b, 1a and 2a exhibited no possible reduction up to −1.2 V and two sequential oxidation steps which have been further investigated with EPR study. Differences in stability and electrochemical behavior of 1a, 1b, 2a and 2b have been correlated with theoretical calculations at DFT level in comparison with long known 1c and 2c. 相似文献
7.
4-aryl-2-amino-6-(4-hydroxy-2-oxo-2H-chromen-3-yl)-pyridin-3-carbonitrile (1), 4-aryl-2-oxo-6-(4-hydroxy-2-oxo-2H-chromen-3-yl)-pyridin-3-carbonitriles (2a-2c), 3-(6-aryl-1,2,5,6- tetrahydro-2-thioxopyrimidin-4-yl)-4-hydroxy-2H-chromen-2-one (3a, 3b) and pyrazol-3-yl-4-hydroxycoumarin derivatives (4a-4c, 5, 6a, 6b, 7a, 7b, and 8a-8c) were prepared in order to measure their % change dopamine release in comparison to amphetamine as reference, using PC-12 cells in different concentrations. In addition, the molecular modeling study of the compounds into 3BHH receptor was also demonstrated. The calculated inhibition constant (ki) implemented in the AutoDock program revealed identical correlation with the experimental results to that obtained binding free energy (ΔGb) as both parameters revealed reasonable correlation coefficients (R2) being 0.51 involving 10 compounds; (1, 2b, 2c, 3a, 3b, 4a, 4b, 6a, and 8c). 相似文献
8.
Mukesh Kumar 《Inorganica chimica acta》2008,361(6):1793-1796
The dicarbonyl and diphosphine complexes of the type (η5-C5H5)Fe(L)2ER3 (L2 = (CO)2 (a), (Ph2P)2CH2 (b); ER3 = CH3 (1a/b); SiMe3 (2a/b), GeMe3 (3a/b), SnMe3 (4a/b)) were synthesized and studied electrochemically. Cyclic voltammetric studies on the dicarbonyl complexes 1a-4a revealed one electron irreversible oxidation processes whereas the same processes for the chelating phosphine series 1b-4b were reversible. The Eox values found for the series 1a-4a were in the narrow range 1.3-1.5 V and in the order Si > Sn ≈ Ge > C; those for 1b-4b (involving replacement of the excellent retrodative π-accepting CO ligands by the superior σ-donor and poorer π-accepting phosphines) have much lower oxidation potentials in the sequence Sn > Si ≈ Ge > C. This latter oxidation potential pattern relates directly to the solution 31P NMR chemical shift data illustrating that stronger donation lowers the Eox for the complexes; however, simple understanding of the trend must await the results of a current DFT analysis of the systems. 相似文献
9.
The ligands bis-(imidazolium) hexafluorophosphate (Himy = -C3N2H3-, imidazolium; R = 1-naphthylmethylene, 1a; 9-anthracenylmethylene, 1b) with an oxoether chain were easily prepared by the reaction of substituted imidazole with the diglycol diiodide, followed by exchange of anions with . 1a and 1b reacted with Ag2O in DMSO or CH3CN to yield [2 + 2] dinuclear Ag(I) NHCs macrocyclic complexes 2a and 2b, which showed much different conformation in solid corresponding to the R- substituent. Carbene transmetalation reactions of 2a-b with Au(SMe2)Cl give dinuclear Au(I) analogs 3a and 3b. The new NHCs complexes were characterized by elemental analyses, 1H NMR, 13C NMR and the structures of 2a-b and 3a were confirmed by X-ray diffraction determination. 相似文献
10.
Kazuhiro Takenaka 《Inorganica chimica acta》2004,357(13):3895-3901
Novel upper-rim modified tetraphosphinocalix[4]arenes (5a-b) adopting 1,3-alternate conformation have been synthesized. Reaction of 5,11,17,23-tetrachloromethyl-25,26,27,28-tetrahydroxycalix[4]arene (1) with Ph2POEt gave 5,11,17,23-tetrakis(diphenylphosphinoylmethyl)-25,26,27,28-tetrahydroxycalix[4]arene (2). Tetra-O-substitution of 2 with n-propyl iodide or benzyl bromide in the presence of K2CO3 carried out to afford 5,11,17,23-tetrakis(diphenylphosphinoylmethyl)-25,26,27,28-tetrapropoxy-(3a) or -benzyloxycalix[4]arene (3b), whereas di-O-substituted calix[4]arene, 5,11,17,23-tetrakis(diphenylphosphinoylmethyl)-25,27-dipropoxy-26,28-dihydroxycalix[4]arene (4), was obtained exclusively when Na2CO3 was used as base. Reduction of 3a-b with PhSiHCl2 afforded 5,11,17,23-tetrakis(diphosphinomethyl)-25,26,27,28-tetrapropoxy-(5a) and -tetrabenzyloxycalix[4]arene (5b). 1H and 13C NMR analysis reveals that the phosphines (5a-b) and the tetra-O-substituted phosphine oxides (3a-b) adopt 1,3-alternate conformation, while the parent tetrahydroxy-(2) and the di-O-propylated phosphine oxide (4) adopt cone-conformation. The X-ray structure indicates that the calix[4]arene moieties in 4 a pinched-cone conformation in solid state. Complexation of the phosphine ligand (5a) with [RuCl2(p-cymene)]2 affords the tetranuclear complexes, [{RuCl2(p-cymene)}2 · 5a] (6), as 1,3-alternate conformer. 相似文献
11.
Gianluca Martelli Antonella Monsignori Mario Orena Samuele Rinaldi Nicola Castellucci Claudia Tomasini 《Amino acids》2012,43(5):2005-2014
Chiral imines 1a,b, already synthesized in our laboratory, were converted in good yield by reduction into the corresponding N-benzyl-γ-lactams 2a,b. Desilylation followed by oxidation of the hydroxymethyl functionality gave the N-benzyl-β-amino acids 5a,b in good yield and high purity. Starting from compound 6a, the corresponding β-peptoid dimer 8 was prepared, together with its derivatives 9 and 10, these latter displaying conformational restriction about the peptide bond, as evidenced by NMR data. 相似文献
12.
13.
Density functional theory (DFT) was used to investigate the nickel- or nickel(0)/zinc- catalyzed decarbonylative addition of phthalic anhydrides to alkynes. All intermediates and transition states were optimized completely at the B3LYP/6-31+G(d,p) level. Calculated results indicated that the decarbonylative addition of phthalic anhydrides to alkynes was exergonic, and the total free energy released was ?87.6 kJ mol?1. In the five-coordinated complexes M4a and M4b, the insertion reaction of alkynes into the Ni-C bond occurred prior to that into the Ni-O bond. The nickel(0)/zinc-catalyzed decarbonylative addition was much more dominant than the nickel-catalyzed one in whole catalytic decarbonylative addition. The reaction channel CA→M1'→T1'→M2'→T2'→M3a'→M4a'→T3a1'→M5a1' →T4a1'→M6a'→P was the most favorable among all reaction pathways of the nickel- or nickel(0)/zinc- catalyzed decarbonylative addition of phthalic anhydrides to alkynes. And the alkyne insertion reaction was the rate-determining step for this channel. The additive ZnCl2 had a significant effect, and it might change greatly the electron and geometry structures of those intermediates and transition states. On the whole, the solvent effect decreased the free energy barriers. Figure
DFT study suggests that NiL4/ZnCl2 (L=PMe3) has higher catalysis than NiL4 in the synthesis of isocoumarin from phthalic anhydrides and alkynes. 相似文献
14.
Complexes of the type (η4-BuC5H5)Fe(CO)2(P) (P = PPh2Py 3, PPhPy24, PPy35; Py = 2-pyridyl) were satisfactorily prepared. Upon treatment of 3 with M(CO)3(EtCN)3 (M = Mo, 6a; W, 6b), the pyridyl N-atom could be coordinated to the metal M, which then eliminates a CO ligand from the Fe-centre and induced an oxidative addition of the endo-C-H of (η4-BuC5H5). This results in a bridged hydrido heterodimetallic complex [(η5-BuC5H4)Fe(CO)(μ-P,N-PPh2Py)(μ-H)M(CO)4] (M = Mo, 7a, 81%; W, 7b, 76%). The reaction of 4 or 5 with 6a,b did not give the induced oxidative addition, although these complexes contain more than one pyridyl N-atom. The reaction of 4 with M(CO)4(EtCN)2 (M = Mo, 9a; W, 9b) produced heterodimetallic complexes [(η4-BuC5H5)Fe(CO)2(μ-P:N,N′-PPhPy2)M(CO)4] (M = Mo, 10a, 81%; W, 10b, 83%). Treatment of 5 with 6a,b gave [(η4-BuC5H5)Fe(CO)2(μ-P:N,N′,N″-PPy3)M(CO)3] (M = Mo, 12a, 96%; W, 12b, 78%). 相似文献
15.
A series of iminopyridine ligands; cyclopropylpyridin-2-ylmethyleneamine (A), cyclopentylpyridin-2-ylmethyleneamine (B), cyclohexylpyridin-2-ylmethyleneamine (C), and cycloheptylpyridin-2-ylmethyleneamine, (D) and their copper(I) complexes, [Cu(L)2]+ (1a-1d) and [Cu(L)(PPh3)2]+ (2a-2d) have been synthesized and characterized by CHN analyses, 1H NMR and IR and UV-Vis spectroscopy. Structures of 1a, 1b, 1c and 2a were determined by X-ray crystallography. The coordination polyhedron about the CuI center in the complexes is best described as a distorted tetrahedron. The dihedral angles between the least-squares planes of the chelate ligands show considerable variation from 86.1° in 1a to 68.3° in 1b, indicating the importance of packing forces in the crystalline environment. The UV-Vis spectra of the complexes are characterized by first metal to ligand charge transfer bands increasing in wavelength with increasing size of the ring substituents in the ligands, except for the cyclopropyl compounds (1a and 2a), in good agreement with the variation of the dihedral angles between the ligand planes. Cyclic voltammetry of the complexes indicates a quasireversible redox behavior for the complexes. The bulkier ligands (PPh3) inhibit the geometric distortion within the oxidized form and the redox potentials of complexes 2a-2d are shifted to more positive values, therefore. 相似文献
16.
Several mononuclear copper complexes 1(a-b) and 2(a-b) supported over sterically demanding [NNO] ligands namely, N-(aryl)-2-[(pyridin-2-ylmethyl)amino]acetamide [aryl = 2,6-diethylphenyl (1) and mesityl (2)], exhibit catecholase-like activity in performing the aerial oxidation of 3,5-di-t-butylcatehol (3,5-DTBC) to 3,5-di-t-butyl-catequinone (3,5-DTBQ) under ambient conditions. The 1(a-b) and 2(a-b) complexes were directly synthesized from the reaction of the respective ligands 1-2 with CuX2·nH2O (X = Cl, NO3, n = 2, 3) in 55-85% yield. Mechanistic insights on the catalytic cycle as obtained by density functional theory studies for a representative complex 1a suggest that an intramolecular hydrogen transfer, from a catechol-OH moiety to a copper bound superoxo moiety, form the rate-determining step of the oxidation process, displaying an activation barrier of 18.3 kcal/mol (ΔG‡) [6.9 kcal/mol in Δ(PE + ZPE)‡ scale]. 相似文献
17.
Mohamed R. E. Aly El-Sayed I. Ibrahim Fakher A. El Shahed Hamdy A. Soliman Zein S. Ibrahim Samir A. M. El-Shazly 《Russian Journal of Bioorganic Chemistry》2012,38(4):428-434
Two derivatives of 2-(4-acetylanilino)quinolines (IIIa, b) were synthesized as scaffolds for synthesis of open chalcone analogues (Va-f) through Claisen-Schmidt condensation with a set of aromatic aldehydes (IVa-d). Derivatives (Va, b) were further manipulated into cyclic ??,??-unsaturated ketones by Michael-addition of acetylacetone and ethylacetoacetate affording derivatives (VI?CVII). Deethoxycarboxylation of derivatives (VIIa, b) afforded cyclohexenons (VIIIa, b) allowing formation of a mini library of ??,??-unsaturated ketones for screening their anticancer and synergistic anticancer effect with doxorubicin using colon cancer cell line (Caco-2). Two open enones, (Vb) and (Ve), showed significant anticancer activity with IC50 of 5.0 and 2.5 ??M respectively. Only one cyclic enone, (VIa) showed synergistic anticancer activity with doxorubicin at 10 ??M. 相似文献
18.
Aldona Beganskiene 《Inorganica chimica acta》2008,361(5):1349-1356
New t-butyl-aryl thioethers where the aryl group is 2,6-bis(phosphino)phenyl have been synthesized. The syntheses were completed via sequential ortho-lithiations of t-butylphenylsulfide, followed by chlorophosphine (ClPR2) quenches; symmetric (2,6-bis(diphenylphosphino)phenyl, (4a)) and unsymmetric (2-diisopropylphosphino-6-diphenylphosphino)phenyl, (4b) aryl groups were obtained. Treatment of 4a with Li or Na naphthalenide yielded 2,6-bis(diphenylphosphino)thiophenol 5. Reactions of 4a or 5 with NiCl2 · 6H2O yielded nickel bis(phosphinothiophenolate) 6. Compounds 4a,b, 5 and 6 were characterized by 1H and 31P NMR, and by mass-spectrometry. In addition, 4a, 5 and 6 were characterized by single crystal X-ray diffraction methods. 相似文献
19.
Rafik Karaman Ghadeer Dokmak Maryam Bader Hussein Hallak Mustafa Khamis Laura Scrano Sabino Aurelio Bufo 《Journal of molecular modeling》2013,19(1):439-452
Density functional theory (DFT) calculations at B3LYP/6-31 G (d,p) and B3LYP/6-311?+?G(d,p) levels for the substituted pyridine-catalyzed isomerization of monomethyl maleate revealed that isomerization proceeds via four steps, with the rate-limiting step being proton transfer from the substituted pyridinium ion to the C=C double bond in INT1. In addition, it was found that the isomerization rate (maleate to fumarate) is solvent dependent. Polar solvents, such as water, tend to accelerate the isomerization rate, whereas apolar solvents, such as chloroform, act to slow down the reaction. A linear correlation was obtained between the isomerization activation energy and the dielectric constant of the solvent. Furthermore, linearity was achieved when the activation energy was plotted against the pK a value of the catalyst. Substituted-pyridine derivatives with high pK a values were able to catalyze isomerization more efficiently than those with low pK a values. The calculated relative rates for prodrugs 1–6 were: 1 (406.7), 2 (7.6?×?106), 3 (1.0), 4 (20.7), 5 (13.5) and 6 (2.2?×?103). This result indicates that isomerizations of prodrugs 1 and 3–5 are expected to be slow and that of prodrugs 2 and 6 are expected to be relatively fast. Hence, prodrugs 2 and 3–5 have the potential to be utilized as prodrugs for the slow release of monomethylfumarate in the treatment of psoriasis and multiple sclerosis. Figure
Substituted pyridine-catalyzed isomerization of monomethylmaleate (prodrug, cis-isomer) to monomethylfumerate (parental drug, trans-isomer) 相似文献
20.
[Rh(CO)2Cl]2 reacts with two mole equivalent of 2-acetylpyridine (a), 3-acetylpyridine (b) and 4-acetylpyridine (c) to afford chelate [Rh(CO)Cl(η2-N∩O)] (1a) and non-chelate [Rh(CO)2Cl(η1-N∼O)] (1b, 1c) complexes, where, N∩O = a, N∼O = b, c. Oxidative addition (OA) of 1a-1c with CH3I and C2H5I yields penta coordinate rhodium(III) complexes, [Rh(COR)ClI(η2-N∩O)] {R = -CH3 (2a); -C2H5 (3a)} and [Rh(COR)(CO)ClI(η1-N∼O)] {R = -CH3 (2b, 2c); -C2H5 (3b, 3c)}. Kinetic study for the reaction of 1a-1c with CH3I indicates a pseudo-first order reaction. The catalytic activity of 1a-1c for the carbonylation of methanol to acetic acid and its ester was evaluated at different initial CO pressures 5, 10 and 20 bar at ∼25 °C and higher turn over numbers (TON = 1581-1654) were obtained compared to commercial Monsanto’s species [Rh(CO)2I2]− (TON = 1000) under the reaction conditions: temperature = 130 ± 1 °C, pressure = 15-32 bar, rpm = 450, time = 1 h and catalyst: substrate = 1: 1900. 相似文献