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1.
A wool‐palladium complex has been found to be able to catalyze the asymmetric hydration of 1‐octene to (S)‐(+)‐2‐octanol and 1‐decene to (R)‐(+)‐2‐decanol under 1 atm N2 and at 70°C. The optical yields were greatly affected by Pd content in wool‐palladium complex, reaction time and so on, when the proper conditions were selected, (S)‐(+)‐2‐octanol and (R)‐(+)‐2‐decanol could be obtained in 83.2 and 75.6%e.e. optical yield respectively. This chiral natural biopolymer‐palladium complex catalyst was very easy to prepare and could be reused several times without appreciable change in catalytic activity. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
2.
Da‐Qing Zhou De‐Jun Zhou Xiao‐Hua Cui Fu‐Ming Wang Mei‐Yu Huang Ying‐Yan Jiang 《先进技术聚合物》2004,15(6):350-354
A new silica‐supported biopolymer‐metal complex, silica‐supported chitosan‐iron‐nickel complex was prepared by a very simple method. This complex catalyst can be used as a catalyst in the asymmetric hydrogenation of propiophenone to (R)‐(+)‐1‐phenyl‐1‐propanol and acetophenone to (R)‐(+)‐1‐phenyl ethanol in 91.7 and 77.7% optical yields, respectively, at 110°C and under 70 kg/cm2 pressure. The catalyst could be reused several times without any remarkable change in the catalytic activity. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
3.
《Helvetica chimica acta》2018,101(4)
As new pyrrole‐modified subporphyrins (PMSubPs) bearing a sulfur‐containing heterocyclic unit, dithiazolosubporphyrin 5 , dithiazinosubchlorin 6 , and oxodithiazinosubchlorin 7 were synthesized from α‐fluorosubchlorophin 2 via α’‐selective nitration with Cu(NO3)2 followed by double SN2 reaction with methyl 3‐mercaptopropionate as a key step. Oxidation of 5 with H2O2 in the presence of a tungsten catalyst afforded S,S‐dioxodithiazolosubporphyrin 8 and nitration of 5 with Cu(NO3)2·3H2O gave β‐nitrodithiazolosubporphyrin 9 or β,β‐dinitrodithiazolosubporphyrins 10a and 10b depending on reaction conditions. In the solid‐states, the dithiazole units in 8 and 9 are almost planar but the dithiazine unit in 6 and the 2‐oxodithiazine unit in 7 are non‐planar. Compared to subchlorophin 1 , dithiazolosubporphyrin 5 possesses a significantly reduced diatropic ring current and a greatly perturbed absorption spectrum showing largely split Q‐like bands at 501 and 660 nm. These perturbed electronic and optical properties of 5 are considerably attenuated in 6 and 7 and completely vanished in 8 , suggesting the importance of disulfide bond for the large perturbation. 相似文献
4.
A new chiral polymer–metal complex, methylsulfo–sodium carboxymethyl–cellulose–Pt complex (MS‐NaCMC‐Pt), has been prepared by the reaction of sodium carboxymethylcellulose with methylsulfonyl chloride and H2PtCl6·6H2, which was found to be able to catalyze the asymmetric hydrogenation of salicyl alcohol to give (1S,2S)‐2‐(hydroxymethyl)‐cyclohexanol at 28 °C and under 1 atm H2, in > 90% product and optical yields, respectively. The catalyst could be reused many times without any remarkable changes in optical catalytic activity. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
5.
The reaction of S‐methylisothiosemicarbazide hydroiodide (=S‐methyl hydrazinecarboximidothioate hydroiodide; 1 ), prepared from thiosemicarbazide by treatment with MeI in EtOH, and aryl isoselenocyanates 5 in CH2Cl2 affords 3H‐1,2,4‐triazole‐3‐selone derivatives 7 in good yield (Scheme 2, Table 1). During attempted crystallization, these products undergo an oxidative dimerization to give the corresponding bis(4H‐1,2,4‐triazol‐3‐yl) diselenides 11 (Scheme 3). The structure of 11a was established by X‐ray crystallography. 相似文献
6.
A series of β‐hydroxynitriles were efficiently synthesized from the regioselective ring opening of oxiranes by cyanide anion in the presence of silica‐bound 3‐{2‐[poly(ethylene glycol)]ethyl}‐substituted 1‐methyl‐1H‐imidazol‐3‐ium bromide (SiO2? PEG? ImBr) as a novel recoverable phase‐transfer catalyst in H2O (Scheme 1 and Table 2). The workup procedure was straightforward, and the catalyst could be reused over four times with almost no loss of catalytic activity and selectivity. 相似文献
7.
Ju‐Hong Miao Ji‐Huo Yang Li‐Yi Chen Bu‐Xin Tu Mei‐Yu Huang Ying‐Yan Jiang 《先进技术聚合物》2004,15(4):221-224
A new chiral polymer‐metal complex, wool‐osmium tetroxide (wool‐OsO4) complex was prepared by a very simple method. This complex was found to be able to catalyze the asymmetric dihydroxylation of allylamine to (R)‐(+)‐3‐amino‐1, 2‐propanediol and allyl chloride to (S)‐(+)‐3‐chloro‐1,2‐propanediol. The optical yields amounted to 83.7 and 57.2%, and the product yields were 80.2 and 68.5% respectively. The experimental results showed that OsO4 content in the complex, reaction time, allylamine/OsO4 molar ratio and solvent all have an effect on the product and optical yields. Additionally, wool‐OsO4 complex catalyst could be reused without any remarkable change in optical catalytic activity. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
8.
Hong Liu Rongjie Yu Kanfu Peng Hongwen Zhao Lian Li Xiongfei Wu 《Electroanalysis》2010,22(21):2577-2586
Through electrodepositing Prussian blue (PB) and chitosan (CS), then casting Pt hollow nanospheres (HN‐Pt) and assembling CA19‐9 antibody on the electrode surface, an immunosensor was achieved. A new signal amplification strategy based on PB and HN‐Pt toward the electrocatalytic reduction of H2O2 was employed when performing the determination. The resulting immunosensor showed a high sensitivity, broad linear response to carbohydrate antigen 19‐9 (CA19‐9) in two ranges from 0.5 to 30 and 30 to 240 U mL?1 with a low detection limit of 0.13 U mL?1 (S/N=3). Moreover, it displayed good reproducibility and stability, and would be potentially attractive for clinical immunoassay of CA19‐9. 相似文献
9.
Shou‐Zhi Pu Gang Liu Bing Chen Ru‐Ji Wang 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(10):o599-o601
The title compound, C27H18F6S2, a novel photochromic hybrid diarylethene derivative containing 2‐ and 3‐thienyl substituents, is one of the most promising photochromic candidates with shorter wavelength for optical storage and other optoelectronic devices. In the crystal structure, the molecule adopts a photoactive antiparallel conformation. The distance between the two reactive C atoms, i.e. the ring C atoms to which the methyl groups are attached, is 3.430 (4) Å. The dihedral angles between the thienyl and adjacent phenyl rings are 26.8 (2) and 33.98 (9)°. 相似文献
10.
Melanie A. Short Roger D. Sommer Alec J. Falzone Tao Huang Walter W. Weare Jennifer L. Roizen 《Acta Crystallographica. Section C, Structural Chemistry》2019,75(6):717-722
While six‐coordinate iron(III) porphyrin complexes with pyridine N‐oxides as axial ligands have been studied as they exhibit rare spin‐crossover behavior, studies of five‐coordinate iron(III) porphyrin complexes including neutral axial ligands are rare. A five‐coordinate pyridine N‐oxide–5,10,15,20‐tetraphenylporphyrinate–iron(III) complex, namely (pyridine N‐oxide‐κO)(5,10,15,20‐tetraphenylporphinato‐κ4N,N′,N′′,N′′′)iron(III) hexafluoroantimonate(V) dichloromethane disolvate, [Fe(C44H28N4)(C5H5NO)][SbF6]·2CH2Cl2, was isolated and its crystal structure determined in the space group P. The porphyrin core is moderately saddled and the Fe—O—N bond angle is 122.08 (13)°. The average Fe—N bond length is 2.03 Å and the Fe—ONC5H5 bond length is 1.9500 (14) Å. This complex provides a rare example of a five‐coordinate iron(III) porphyrin complex that is coordinated to a neutral organic ligand through an O‐monodentate binding mode. 相似文献
11.
Andrzej Gzella Maria D. Rozwadowska 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(8):981-982
The absolute configuration of the title compound, alternatively called (+)‐(4,5‐dihydro‐2,5‐diphenyloxazol‐4‐yl)methanol, C16H15NO2, has been confirmed as 4S,5S. The hydroxymethyl group and phenyl ring at the asymmetric C atoms exhibit β and α orientations, respectively. The exocyclic C—C bonds at the asymmetric C atoms are mutually anticlinal (?ac). The hydroxyl group and the N atom of the oxazoline ring are involved in an intermolecular hydrogen bond leading to chains of molecules. 相似文献
12.
Catalytic behaviors of silica‐supported natural biopolymer–oxalic acid–Pt complexes in hydrogenation
Three kinds of natural biopolymers, gelatin, alginic acid and sodium carboxymethylcellulose (NaCMC), were reacted with oxalic acid in the presence of silica to yield complexes on the surface of silica, followed by reaction with H2PtCl6 6H2O to form Pt complexes, SiO2–gelatin–(COOH)2–Pt, SiO2–alginic acid–(COOH)2–Pt, and SiO2–NaCMC–(COOH)2–Pt, respectively. These complexes were able to catalyze the hydrogenation of 1‐heptene to give n‐heptane and that of nitrobenzene to give aniline at 25 °C and under 1 atm H2 in 100% yields. Experimental data show that the catalysts were very stable and could be reused without any remarkable change in catalytic activity. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
13.
Qiang Yu Diansheng Liu Xiangjun Li Jianfeng Li 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(10):856-859
As representative porphyrin model compounds, the structures of `picket‐fence' porphyrins have been studied intensively. The title solvated complex salt {systematic name: (4,7,13,16,21,24‐hexaoxa‐1,10‐diazabicyclo[8.8.8]hexacosane)potassium(I) [5,10,15,20‐tetrakis(2‐tert‐butanamidophenyl)porphyrinato]iron(II) n‐hexane monosolvate}, [K(C18H36N2O6)][Fe(C64H64N8O4)Cl]·C6H14 or [K(222)][Fe(TpivPP)Cl]·C6H14 [222 is cryptand‐222 or 4,7,13,16,21,24‐hexaoxa‐1,10‐diazabicyclo[8.8.8]hexacosane, and TpivPP is meso‐α,α,α,α‐tetrakis(o‐pivalamidophenyl)porphyrinate(2−)], [K(222)][Fe(TpivPP)Cl]·C6H14, is a five‐coordinate high‐spin iron(II) picket‐fence porphyrin complex. It crystallizes with a potassium cation chelated inside a cryptand‐222 molecule; the average K—O and K—N distances are 2.81 (2) and 3.05 (2) Å, respectively. One of the protecting tert‐butyl pickets is disordered. The porphyrin plane presents a moderately ruffled distortion, as suggested by the atomic displacements. The axial chloride ligand is located inside the molecular cavity on the hindered porphyrin side and the Fe—Cl bond is tilted slightly off the normal to the porphyrin plane by 4.1°. The out‐of‐plane displacement of the metal centre relative to the 24‐atom mean plane (Δ24) is 0.62 Å, indicating a noticeable doming of the porphyrin core. 相似文献
14.
Lauren A. Brown Francis S. Wekesa Daniel K. Unruh Michael Findlater Brian K. Long 《Journal of polymer science. Part A, Polymer chemistry》2017,55(17):2824-2830
The α‐diimine‐ligated Fe‐complex, BIAN‐Fe(C6H6) , was synthesized and evaluated for the polymerization of l ‐lactide. Characterization of BIAN‐Fe(C6H6) reveals that it is redox non‐innocent and suggests that it is an Fe(I) species bearing a radical‐anionic ligand. We will demonstrate that BIAN‐Fe(C6H6) is active for the ring‐opening polymerization of l ‐lactide, and that polymer is produced with, or without, the use of an added external initiator. Interestingly, very high molecular weight polymers are produced in the absence of external initiator whereas polymer molecular weights that agree with theoretical calculations are produced in the presence of external initiator. To the best of our knowledge, BIAN‐Fe(C6H6) is the first Fe‐based α‐diimine catalyst reported to be active for the polymerization of l ‐lactide. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2824–2830 相似文献
15.
Zhong-Xuan Xu Guo-Guo Chen Li-Feng Li 《Acta Crystallographica. Section C, Structural Chemistry》2020,76(2):125-132
The reactions of (R)‐ and (S)‐4‐(1‐carboxyethoxy)benzoic acid (H2CBA) with 1,3‐bis(2‐methyl‐1H‐imidazol‐1‐yl)benzene (1,3‐BMIB) ligands afforded a pair of homochiral coordination polymers (CPs), namely, poly[[[μ‐1,3‐bis(2‐methyl‐1H‐imidazol‐1‐yl)benzene][μ‐(S)‐4‐(1‐carboxylatoethoxy)benzoato]zinc(II)] monohydrate], {[Zn(C10H8O5)(C14H14N4)]·H2O}n or {[Zn{(S)‐CBA}(1,3‐BMIB)]·H2O}n ( 1‐L ), and poly[[[μ‐1,3‐bis(2‐methyl‐1H‐imidazol‐1‐yl)benzene][μ‐(R)‐4‐(1‐carboxylatoethoxy)benzoato]zinc(II)] monohydrate] ( 1‐D ). Three kinds of helical chains exist in compounds 1‐D and 1‐L , which are constructed from ZnII atoms, 1,3‐BMIB ligands and/or CBA2? ligands. When the as‐synthesized crystals of 1‐L and 1‐D were further heated in the mother liquor or air, poly[[μ‐1,3‐bis(2‐methyl‐1H‐imidazol‐1‐yl)benzene][μ‐(S)‐4‐(1‐carboxylatoethoxy)benzoato]zinc(II)], [Zn(C10H8O5)(C14H14N4)]n or [Zn{(S)‐CBA}(1,3‐BMIB)]n ( 2‐L ), and poly[[μ‐1,3‐bis(2‐methyl‐1H‐imidazol‐1‐yl)benzene][μ‐(R)‐4‐(1‐carboxylatoethoxy)benzoato]zinc(II)] ( 2‐D ) were obtained, respectively. The single‐crystal structure analysis revealed that 2‐L and 2‐D only contained one type of helical chain formed by ZnII atoms and 1,3‐BMIB and CBA2? ligands, which indicated that the helical chains were reconstructed though solid‐to‐solid transformation. This result not only means the realization of helical transformation, but also gives a feasible strategy to build homochiral CPs. 相似文献
16.
Nardjes Mouas Toma Jean‐Claude Daran Hocine Merazig Eric Manoury 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(5):460-464
In our ongoing development of ferrocene ligands, 1‐dimethylamino‐2‐(diphenylphosphinothioyl)ferrocene is being used as a convenient building block to obtain racemic or enantiomerically pure ligands. Using this building block in large excess allowed the formation of several by‐products, two of which have already been reported; the structure of a third by‐product, namely 1‐(diphenylphosphinothioyl)‐2‐{[(diphenylphosphinothioyl)sulfanyl]methyl}ferrocene, [Fe(C5H5)(C30H25P2S3)], is presented here. The crystal structure is built up from a ferrocene unit, with one of the cyclopentadienyl (Cp) rings substituted in the 1‐ and 2‐positions by a protected diphenylphosphinothioyl group and a [(diphenylphosphinothioyl)sulfanyl]methyl fragment, –CH2SP(=S)Ph2. There are C—H...S interactions which result in the formation of chains parallel to the c axis. After desulfurization, the crude material was then reacted with Pd and Pt (M) precursors [MCl2(CH3CN)2] to yield two isostructural dinuclear complexes arranged around twofold axes, namely (R,R/S,S)‐bis{μ‐[2‐(diphenylphosphanyl)ferrocen‐1‐yl]methanethiolato‐κ3P,S:S}bis[chloridopalladium(II)] pentane disolvate, [Pd2{Fe(C5H5)(C18H15PS)}2Cl2]·2C5H12, and the platinum(II) analogue, (R,R/S,S)‐bis{μ‐[2‐(diphenylphosphanyl)ferrocen‐1‐yl]methanethiolato‐κ3P,S:S}bis[chloridoplatinum(II)] toluene monosolvate, [Pt2{Fe(C5H5)(C18H15PS)}2Cl2]·C7H8, in which the two metal atoms present a slightly distorted square‐planar geometry formed by two bridging S atoms and P and Cl atoms. The P,S‐chelating ligand results from the rupture of one of the P—S bonds in the starting ligand. These dinuclear complexes display a butterfly geometry. Surprisingly, only the (R,R/S,S) diastereoisomer has been isolated. 相似文献
17.
Anthony Linden Agnieszka Majchrzak Jovita Cavegn Grzegorz Mloston Heinz Heimgartner 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(8):o480-o484
The four oligosulfanes, bis(1‐chloro‐2,2,4,4‐tetramethyl‐3‐oxocyclobutan‐1‐yl)disulfane, C16H24Cl2O2S2, (III), 1,3‐bis(1‐chloro‐2,2,4,4‐tetramethyl‐3‐oxocyclobutan‐1‐yl)trisulfane, C16H24Cl2O2S3, (V), 1,4‐bis(1‐chloro‐2,2,4,4‐tetramethyl‐3‐oxocyclobutan‐1‐yl)tetrasulfane, C16H24Cl2O2S4, (VII), and 1,6‐bis(1‐chloro‐2,2,4,4‐tetramethyl‐3‐oxocyclobutan‐1‐yl)hexasulfane, C16H24Cl2O2S6, (VIII), all have similar geometric parameters, with the C—C bond lengths involving the chloro‐substituted cyclobutanyl C atom being elongated to about 1.59 Å. There are two molecules in the asymmetric units of the tri‐ and tetrasulfanes, and the molecules in the latter compound have local C2 symmetry. The molecule of the hexasulfane has crystallographic C2 symmetry. Most of the cyclobutanyl rings are not perfectly planar and have slight but varying degrees of distortion towards a flattened tetrahedron. The polysulfane chain in each structure has a helical conformation, with each additional S atom in the chain adding approximately one quarter of a turn to the helix. 相似文献
18.
NH4Fe(SO4)2 was found to be a mild and effective catalyst for the selective synthesis of 2‐aryl‐1‐arylmethyl‐1H‐1,3‐benzimidazoles under solvent‐free conditions. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
19.
The (chitosan‐Schiff base)cobalt(II) complex was found to be an efficient catalyst for the oxidative carbonylation (CO/O2) of 2‐aminoalkan‐1‐ols 1 to give oxazolidin‐2‐ones 2 , in the presence of NaI. The effects of promoters, temperature, solvents, and other reaction conditions were investigated in this study. 相似文献
20.
Eric P. Kelson Norman S. Dean Edgar Algarín 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(3):m108-m110
The title compound, [Ru(C6H6NO2)2(C15H11N3)(H2O)]·CH3CN·H2O, is a transfer hydrogenation catalyst supported by nitrogen‐donor ligands. This octahedral RuII complex features rare monodentate coordination of 3‐methoxy‐2‐pyridonate ligands and interligand S(6)S(6) hydrogen bonding. Comparison of the title complex with a structural analog with unsubstituted 2‐pyridonate ligands reveals subtle differences in the orientation of the ligand planes. 相似文献