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1.
The reaction of isoprene with aniline, catalyzed by the Pd(acac)2-(RO)3P-CF3CO2H system, 1 : 4 : 4 [R = Me, Et; acac = (CH3CO)2CH], in MeCN provides N-(3-methylbut-2-en-1-yl)aniline with a high selectivity (up to 84%) and a nearly quantitative yield (75%). At 1 : 4 : 20 and 1 : 4 : 40 molar component ratios in the catalytic system, up to 28–31% of N,N-(2,3-dimethylprop-2-en-1-yl)aniline is formed. Telomeric reaction products appear at 1 : 2 : 4 and 1 : 1 : 10 ratios.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 6, 2005, pp. 963–968.Original Russian Text Copyright © 2005 by Petrushkina, Mysova, Orlinkov.  相似文献   

2.
Styrene oligomerization in the presence of Pd(acac)2+PPh3+BF3OEt2 catalytic system (acac—acetylacetonate) has been studied. Styrene conversion at optimum conditons (T=343 K, B/Pd=7, P/Pd=2) was as high as 75,000 mol of C3H3 per mol of Pd in 7 h with a selectivity to dimers, mostly 1,3-diphenylbut-1-ene, up to 93%.  相似文献   

3.
Isoprene and aniline have been reacted on the catalytic system Pd(acac)2-Ph3P to form a mixture of isomeric telomers: N-(dimethyloctadien-2,7-yl-1)anilines and N-(dimethyloctadien-1,7-yl-3)anilines but on the catalytic system Pd(acac)2-Ph3P-CF3COOH the main product is a mixture of N-(methylbuten-2-yl)aniline adducts. The reaction between N-methylaniline and isoprene on the latter catalyst also gives a mixture of N-methyl and N-(methylbuten-2-yl)aniline adducts.A. N. Nesmeyanov Institute of Organoelemental Compounds, Russian Academy of Sciences, 117813 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1794–1798, August, 1992.  相似文献   

4.
Chemoselective reduction of the C=C bond in a variety of α,β‐unsaturated carbonyl compounds using supported palladium nanoparticles is reported. Three different heterogeneous catalysts were compared using 1 atm of H2: 1) nano‐Pd on a metal–organic framework (MOF: Pd0‐MIL‐101‐NH2(Cr)), 2) nano‐Pd on a siliceous mesocellular foam (MCF: Pd0‐AmP‐MCF), and 3) commercially available palladium on carbon (Pd/C). Initial studies showed that the Pd@MOF and Pd@MCF nanocatalysts were superior in activity and selectivity compared to commercial Pd/C. Both Pd0‐MIL‐101‐NH2(Cr) and Pd0‐AmP‐MCF were capable of delivering the desired products in very short reaction times (10–90 min) with low loadings of Pd (0.5–1 mol %). Additionally, the two catalytic systems exhibited high recyclability and very low levels of metal leaching.  相似文献   

5.
《Mendeleev Communications》2023,33(2):184-187
Acetylacetonate palladium(II) complexes bearing pyridinyl imine ligands [Pd(acac)(L)]BF4 were synthesized via nitrile displacement in [Pd(acac)(MeCN)2]BF4 by the bidentate ligands L of type 2-C5H4N–CH=N–(CH2)nOMe or 2-C5H4N–CH=N–Ar. The structures of complexes were analyzed by X-ray diffractometry, NMR, and DFT. The complexes catalyze hydroamination of phenylacetylene with aniline to give the Markovnikov imine product as well as polymerization of norbornene.  相似文献   

6.
A new motif for infinite metal atom wires with tunable compositions and properties is developed based on the connection between metal paddlewheel and square planar complex moieties. Two infinite Pd chain compounds, [Pd4(CO)4(OAc)4Pd(acac)2] 1 and [Pd4(CO)4(TFA)4Pd(acac)2] 2 , and an infinite Pd? Pt heterometallic chain compound, [Pd4(CO)4(OAc)4Pt(acac)2] 3 , are identified by single‐crystal X‐ray diffraction analysis. In these new structures, the paddlewheel moiety is a Pd four‐membered ring coordinated by bridging carboxylic ligands and μ2 carbonyl ligands. The planar moiety is either Pd(acac)2 or Pt(acac)2 (acac=acetylacetonate). These moieties are connected by metallophilic interactions. The results showed that these one‐dimensional metal wire compounds have photoluminescent properties that are tunable by changing ligands and metal ions. 3 can also serve as a single source precursor for making Pd4Pt bimetallic nanostructures with precise control of metal composition.  相似文献   

7.
A new range of CF3‐substituted aminomethyldiphosphine (P―C―N) ligands ((C6H5)2PCH2)2NR (R = ―C6H4(2‐CF3) ( 1 ), ―C6H4(3‐CF3) ( 1b ) has been synthesized from 2‐(trifluoromethyl)aniline and 3‐(trifluoromethyl)aniline with diphenylphosphine. The aminomethyldiphosphine ligands were reacted with Pd(cod)Cl2 to give corresponding metal complexes, PdLCl2 ( 2a , 2b ). The aminomethyldiphosphine–palladium compounds were characterized by utilizing several methods including NMR (1H, 13C, 31P) and elemental analysis. These compounds were used as catalysts in Suzuki cross‐coupling reaction of aryl chlorides and bromides. The effect of base was also investigated in this current project. CF3‐substituted aminomethyldiphosphine–palladium complexes were found to be efficient catalysts in Suzuki cross‐coupling reaction of activated and deactivated aryl boronic acids. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

8.
Tetrakis(p‐tolyl)oxalamidinato‐bis[acetylacetonatopalladium(II)] ([Pd2(acac)2(oxam)]) reacted with Li–C≡C–C6H5 in THF with formation of [Pd(C≡C–C6H5)4Li2(thf)4] ( 1a ). Reaction of [Pd2(acac)2(oxam)] with a mixture of 6 equiv. Li–C≡C–C6H5 and 2 equiv. LiCH3 resulted in the formation of [Pd(CH3)(C≡C–C6H5)3Li2(thf)4] ( 2 ), and the dimeric complex [Pd2(CH3)4(C≡C–C6H5)4Li4(thf)6] ( 3 ) was isolated upon reaction of [Pd2(acac)2(oxam)] with a mixture of 4 equiv. Li–C≡C–C6H5 and 4 equiv. LiCH3. 1 – 3 are extremely reactive compounds, which were isolated as white needles in good yields (60–90%). They were fully characterized by IR, 1H‐, 13C‐, 7Li‐NMR spectroscopy, and by X‐ray crystallography of single crystals. In these compounds Li ions are bonded to the two carbon atoms of the alkinyl ligand. 1a reacted with Pd(PPh3)4 in the presence of oxygen to form the already known complexes trans‐[Pd(C≡C–C6H5)2(PPh3)2] and [Pd(η2‐O2)(PPh3)2]. In addition, 1a is an active catalyst for the Heck coupling reaction, but less active in the catalytic Sonogashira reaction.  相似文献   

9.
Dinuclear Palladium(II), Platinum(II), and Iridium(III) Complexes of Bis[imidazol‐4‐yl]alkanes The reaction of bis(1,1′‐triphenylmethyl‐imidazol‐4‐yl) alkanes ((CH2)n bridged imidazoles L(CH2)nL, n = 3–6) with chloro bridged complexes [R3P(Cl)M(μ‐Cl)M(Cl)PR3] (M = Pd, Pt; R = Et, Pr, Bu) affords the dinuclear compounds [Cl2(R3P)M–L(CH2)nL–M(PR3)Cl2] 1 – 17 . The structures of [Cl2(Et3P)Pd–L(CH2)3L–Pd(PEt3)Cl2] ( 1 ), [Cl2(Bu3P)Pd–L(CH2)4L–Pd(PBu3)Cl2] ( 10 ), [Cl2(Et3P)Pd–L(CH2)5L–Pd(PEt3)Cl2] ( 3 ), [Cl2(Et3P)Pt–L(CH2)3L–Pt(PEt3)Cl2] ( 13 ) with trans Cl–M–Cl groups were determined by X‐ray diffraction. Similarly the complexes [Cl2(Cp*)Ir–L(CH2)nL–Ir(Cp*)Cl2] (n = 4–6) are obtained from [Cp*(Cl)Ir(μ‐Cl)2Ir(Cl)Cp*] and the methylene bridged bis(imidazoles).  相似文献   

10.
PdPtZn and PdZn nanoparticle (NP) thin films were synthesized by the reduction of [PdCl2(cod)], [PtCl2(cod)] (cod = cis,cis‐1,5‐cyclooctadiene) and [Zn(acac)2] (acac = acetylacetonate) complexes at an oil–water interface. The structure and morphology of the as‐prepared NPs were characterized with X‐ray diffraction, transmission electron microscopy and energy dispersive analysis of X‐rays. Catalytic activity of the prepared NPs was investigated in the Suzuki–Miyaura cross‐coupling reaction in H2O–EtOH and various micellar media systems such as cetyltrimethylammonium bromide (cationic surfactant), sodium dodecylsulfate (anionic surfactant) and Pluronic P123 (non‐ionic surfactant). PdPtZn and PdZn thin films exhibited higher catalytic activity compared to Pd thin film in the Suzuki–Miyaura coupling reaction due to the appropriate interaction between palladium, platinum and zinc metals. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

11.
The system Pd(OAc)2/BQ/Co(acac)3 (BQ=benzoquinone), in combination with tetrabutylammonium bromide (TBAB) as a surfactant agent and a chelating ligand such as 2,9-dimethyl-1,10-phenanthroline (dmphen) or 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (dmdpphen), is an efficient catalyst for the oxidative carbonylation of phenol to diphenyl carbonate (DPC). The best results have been obtained using the system Pd(OAc)2/BQ/Co(acac)3/dmphen=1/30/8/5 (molar ratio) in which [Pd]=10−3 mol l−1 and TBAB/Pd=60/1. This system gives the maximum productivity of 700 mol DPC/mol Pd h at 135°C and under Ptot=60 atm (CO/O2=10/1 molar ratio). The role of each component of the catalytic system is discussed and a catalytic cycle is proposed.  相似文献   

12.
This study describes the synthesis of PdCu, PdCu/reduced graphene oxide and PtPdCu nanoparticle thin films via a simple reduction of organometallic precursors including [PtCl2(cod)] and [PdCl2(cod)] (cod = cis ,cis ‐1,5‐cyclooctadiene) complexes, in the presence of [Cu(acac)2] (acac = acetylacetonate) complex at toluene–water interface. The structure and morphology of the thin films were characterized using energy‐dispersive analysis of X‐rays, X‐ray diffraction and transmission electron microscopy techniques. Our studies show that all of these nanoparticles are suitable for the Suzuki–Miyaura coupling (SMC) reaction in water. PtPdCu and PdCu thin films showed higher catalytic activity compared to Pd thin film in the SMC reaction due to the appropriate interaction among palladium, platinum and copper metals.  相似文献   

13.
The η2‐thio‐indium complexes [In(η2‐thio)3] (thio = S2CNC5H10, 2 ; SNC4H4, (pyridine‐2‐thionate, pyS, 3 ) and [In(η2‐pyS)22‐acac)], 4 , (acac: acetylacetonate) are prepared by reacting the tris(η2‐acac)indium complex [In(η2‐acac)3], 1 with HS2CNC5H10, pySH, and pySH with ratios of 1:3, 1:3, and 1:2 in dichloromethane at room temperature, respectively. All of these complexes are identified by spectroscopic methods and complexes 2 and 3 are determined by single‐crystal X‐ray diffraction. Crystal data for 2 : space group, C2/c with a = 13.5489(8) Å, b = 12.1821(7) Å, c = 16.0893(10) Å, β = 101.654(1)°, V = 2600.9(3) Å3, and Z = 4. The structure was refined to R = 0.033 and Rw = 0.086; Crystal data for 3 : space group, P21 with a = 8.8064 (6) Å, b = 11.7047 (8) Å, c = 9.4046 (7) Å, β = 114.78 (1)°, V = 880.13(11) Å3, and Z = 2. The structure was refined to R = 0.030 and Rw = 0.061. The geometry around the metal atom of the two complexes is a trigonal prismatic coordination. The piperidinyldithiocarbamate and pyridine‐2‐thionate ligands, respectively, coordinate to the indium metal center through the two sulfur atoms and one sulfur and one nitrogen atoms, respectively. The short C‐N bond length in the range of 1.322(4)–1.381(6) Å in 2 and C‐S bond length in the range of 1.715(2)–1.753(6) Å in 2 and 3 , respectively, indicate considerable partial double bond character.  相似文献   

14.
Tris(acetylacetonato)ruthenium(III)(Ru(acac)3) was synthesized with RuCl3·nH2O and acetylacetone as raw materials. The structure of Ru(acac)3 was identified by FI-IR, 1H NMR, 13C NMR, and elemental analysis. It was used in the catalytic hydrogen transfer hydrogenation of nitrobenzene with sodium formate as hydrogen donor. The effects of reaction conditions on the process, such as temperature, time, dosage of catalyst, and kinds of hydrogen donor, were investigated. The optimal reaction parameters were determined as follows: 80 °C, 4.0 h, the substrate nitrobenzene 20 mL, sodium formate 27.20 g, Ru(acac)3 0.96 g, the conversion of nitrobenzene is 100.0 %, the yield of aniline and the selectivity to aniline are 96.65 %. The reaction mechanism is proposed and analyzed. It exhibited excellent catalytic properties in the hydrogen transfer hydrogenation of nitrobenzene to aniline.  相似文献   

15.
A series of Zn (II), Pd (II) and Cd (II) complexes, [(L) n MX 2 ] m (L = L‐a–L‐c; M = Zn, Pd; X = Cl; M = Cd; X = Br; n, m = 1 or 2), containing 4‐methoxy‐N‐(pyridin‐2‐ylmethylene) aniline ( L‐a ), 4‐methoxy‐N‐(pyridin‐2‐ylmethyl) aniline ( L‐b ) and 4‐methoxy‐N‐methyl‐N‐(pyridin‐2‐ylmethyl) aniline ( L‐c ) have been synthesized and characterized. The X‐ray crystal structures of Pd (II) complexes [L 1 PdCl 2 ] (L = L‐b and L‐c) revealed distorted square planar geometries obtained via coordinative interaction of the nitrogen atoms of pyridine and amine moieties and two chloro ligands. The geometry around Zn (II) center in [(L‐a)ZnCl 2 ] and [(L‐c)ZnCl 2 ] can be best described as distorted tetrahedral, whereas [(L‐b) 2 ZnCl 2 ] and [(L‐b) 2 CdBr 2 ] achieved 6‐coordinated octahedral geometries around Zn and Cd centers through 2‐equivalent ligands, respectively. In addition, a dimeric [(L‐c)Cd(μ ‐ Br)Br] 2 complex exhibited typical 5‐coordinated trigonal bipyramidal geometry around Cd center. The polymerization of methyl methacrylate in the presence of modified methylaluminoxane was evaluated by all the synthesized complexes at 60°C. Among these complexes, [(L‐b)PdCl 2 ] showed the highest catalytic activity [3.80 × 104 g poly (methyl methacrylate) (PMMA)/mol Pd hr?1], yielding high molecular weight (9.12 × 105 g mol?1) PMMA. Syndio‐enriched PMMA (characterized using 1H‐NMR spectroscopy) of about 0.68 was obtained with Tg in the range 120–128°C. Unlike imine and amine moieties, the introduction of N‐methyl moiety has an adverse effect on the catalytic activity, but the syndiotacticity remained unaffected.  相似文献   

16.
Conclusions Aromatic amides react with butadiene in the presence of Pd(acac)2-Ph3P-AlEt3 (1:3:4) in DMF, and aliphatic amides react with the diene in the presence of Pd(acac)2-Ph3P-CO2-NH2 (1:10:192:438) in N-methylpyrrolidone-2 to form primarily N-2,7-octadienylamides.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 821–828, April, 1988.  相似文献   

17.
The primary hydroxy groups of head‐tail and head‐head bis(sugar)‐based crown ethers ( 1 and 3 , respectively) were acylated by (EtO)2P(O)Cl and Ph2P(O)Cl in a selective manner. Cation binding ability of the bis‐phosphorylated and phosphinylated macrocycles ( 2 and 4 ) was evaluated by the picrate extraction method. Introduction of the P‐moieties led to increase of the extraction ability without significant selectivity. © 2000 John Wiley & Sons, Inc. Heteroatom Chem 11:267–270, 2000  相似文献   

18.
Bis(acetylacetonate)alumo‐oxo‐tetraphenyldisiloxane‐metal(II) dihydrates [(acac)2Al(O–SiPh2–O–SiPh2–O)]2M(H2O)2 (M = Mg, Fe, Co, Ni) were obtained from the corresponding acetyl‐acetonate‐dihydrates (acac)2M(H2O)2 by reaction with the alumosiloxane [O–Ph2Si–O–SiPh2–O]4Al4(OH)4. These new compounds display two acac ligands at the aluminum atoms as well as disilatrioxy chains linking the two aluminum atoms forming a (Al–O–Si–O–Si–O)2 cycle (X‐ray structure analyses). Within this cycle the divalent metal ions M2+, to which two water molecules in trans positions are linked, are installed in almost planar MO4 coordination spheres. Using water free (acac)2Ni a different product forms: both reactants combine in a 2:1 ratio to yield [O–Ph2Si–O–SiPh2–O]4Al4(OH)2O(OH2)Ni2(acac)4. Here, three of the acac ligands were transposed to the aluminum atoms. The nickel atoms are in a distorted octahedral coordination mode from oxygen atoms of the ligands. When iron(III)tris(acetylacetonate) reacts with the alumosiloxane [O–Ph2Si–O–SiPh2–O]3Al2O(OH)Fe2(acac)3 was isolated, in which the two iron atoms still display one of the acac ligands. One of the aluminum atoms is in a tetrahedral oxygen environment, whereas the other is in the center of a trigonal bi‐pyramid formed of oxygen atoms either of the siloxane or of acac. The iron atoms have five‐ or sixfold coordination from oxygen atoms of siloxane, acac, hydroxide or oxide.  相似文献   

19.
The structures of two 1:1 proton‐transfer red–black dye compounds formed by reaction of aniline yellow [4‐(phenyldiazenyl)aniline] with 5‐sulfosalicylic acid and benzenesulfonic acid, and a 1:2 nontransfer adduct compound with 3,5‐dinitrobenzoic acid have been determined at either 130 or 200 K. The compounds are 2‐(4‐aminophenyl)‐1‐phenylhydrazin‐1‐ium 3‐carboxy‐4‐hydroxybenzenesulfonate methanol solvate, C12H12N3+·C7H5O6S·CH3OH, (I), 2‐(4‐aminophenyl)‐1‐phenylhydrazin‐1‐ium 4‐(phenyldiazenyl)anilinium bis(benzenesulfonate), 2C12H12N3+·2C6H5O3S, (II), and 4‐(phenyldiazenyl)aniline–3,5‐dinitrobenzoic acid (1/2), C12H11N3·2C7H4N2O6, (III). In compound (I), the diazenyl rather than the aniline group of aniline yellow is protonated, and this group subsequently takes part in a primary hydrogen‐bonding interaction with a sulfonate O‐atom acceptor, producing overall a three‐dimensional framework structure. A feature of the hydrogen bonding in (I) is a peripheral edge‐on cation–anion association also involving aromatic C—H...O hydrogen bonds, giving a conjoint R12(6)R12(7)R21(4) motif. In the dichroic crystals of (II), one of the two aniline yellow species in the asymmetric unit is diazenyl‐group protonated, while in the other the aniline group is protonated. Both of these groups form hydrogen bonds with sulfonate O‐atom acceptors and these, together with other associations, give a one‐dimensional chain structure. In compound (III), rather than proton transfer, there is preferential formation of a classic R22(8) cyclic head‐to‐head hydrogen‐bonded carboxylic acid homodimer between the two 3,5‐dinitrobenzoic acid molecules, which, in association with the aniline yellow molecule that is disordered across a crystallographic inversion centre, results in an overall two‐dimensional ribbon structure. This work has shown the correlation between structure and observed colour in crystalline aniline yellow compounds, illustrated graphically in the dichroic benzenesulfonate compound.  相似文献   

20.
A series of palladium(II) thiosaccharinates with triphenylphosphane (PPh3), bis(diphenylphosphanyl)methane (dppm), and bis(diphenylphosphanyl)ethane (dppe) have been prepared and characterized. From mixtures of thiosaccharin, Htsac, and palladium(II) acetylacetonate, Pd(acac)2, the palladium(II) thiosaccharinate, Pd(tsac)2 (tsac: thiosaccharinate anion) ( 1 ) was prepared. The reaction of 1 with PPh3, dppm, and dppe leads to the mononuclear species Pd(tsac)2(PPh3)2 · MeCN ( 2 ), [Pd(tsac)2(dppm)] ( 3 ), Pd(tsac)2(dppm)2 ( 4 ), and [Pd(tsac)2(dppe)] · MeCN ( 5 ). Compounds 2 , 4 , and 5 have been prepared also by the reaction of Pd(acac)2 with the corresponding phosphane and Htsac. All the new complexes have been characterized by chemical analysis, UV/Vis, IR, and Raman spectroscopy. Some of them have been also characterized by NMR spectroscopy. The crystalline structures of complexes 3 , and 5 have been studied by X‐ray diffraction techniques. Complex 3 crystallizes in the monoclinic space group P21/n with a = 16.3537(2), b = 13.3981(3), c = 35.2277(7) Å, β = 91.284(1)°, and Z = 8 molecules per unit cell, and complex 5 in P21/n with a = 10.6445(8), b = 26.412(3), c = 15.781(2) Å, β = 107.996(7)°, and Z = 4. In compounds 3 and 5 , the palladium ions are in a distorted square planar environment. They are closely related, having two sulfur atoms of two thiosaccharinate anions, and two phosphorus atoms of one molecule of dppm or dppe, respectively, bonded to the PdII atom. The molecular structure of complex 3 is the first reported for a mononuclear PdII‐dppm‐thionate system.  相似文献   

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