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1.
In the presence of CuCl2, N‐(2′, 4′‐dienyl)‐2‐alkynamides can be converted to α‐alkylidene‐σ‐butyrolactams under the catalysis of palladium(II). In this reaction, CuCl2 is used to oxidize Pd(0) to regenerate Pd(II), or the carbon‐palladium bond is quenched by the oxidative cleavage reaction of CuCl2. 相似文献
2.
Investigation of the Catalytic Activity of a 2‐Phenylidenepyridine Palladium(II) Complex Bearing 4,5‐Dicyano‐1,3‐bis(mesityl)imidazol‐2‐ylidene in the Mizoroki‐Heck Reaction
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The phenylidenepyridine (ppy) palladacycles [PdCl(ppy)(IMes)] ( 4 ) [IMes = 1,3‐bis(mesityl)imidazol‐2‐ylidene] and [PdCl(ppy){(CN)2IMes}] ( 6 ) [(CN)2IMes = 4,5‐dicyano‐1,3‐bis(mesityl)imidazol‐2‐ylidene] were prepared by facile two step syntheses, starting with the reaction of palladium(II) chloride with 2‐phenylpyridine followed by subsequent addition of the NHC ligand to the precatalyst precursor [PdCl(ppy)]2. Suitable crystals for the X‐ray analysis of the complexes 4 and 6 were obtained. It was shown that 6 has a shorter NHC‐palladium bond than the IMes complex 4 . The difference of the palladium carbene bond lengths based on the higher π‐acceptor strength of (CN)2IMes in comparison to IMes. Thus, (CN)2IMes should stabilize the catalytically active central palladium atom better than IMes. As a measure for the π‐acceptor strength of (CN)2IMes compared to IMes, the selone (CN)2IMes · Se ( 7 ) was prepared and characterized by 77Se‐NMR spectroscopy. The π‐acceptor strength of 7 was illuminated by the shift of its 77Se‐NMR signal. The 77Se‐NMR signal of 7 was shifted to much higher frequencies than the 77Se‐NMR signal of IMes · Se. Catalytic experiments using the Mizoroki‐Heck reaction of aryl chlorides with n‐butyl acrylate showed that 6 is the superior performer in comparison to 4 . Using complex 6 , an extensive substrate screening of 26 different aryl bromides with n‐butyl acrylate was performed. Complex 6 is a suitable precatalyst for para‐substituted aryl bromides. The catalytically active species was identified by mercury poisoning experiments to be palladium nanoparticles. 相似文献
3.
Anthony L. Spek Johannes Canisius Hans Preut Norbert Krause 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1065-1066
The title compound, di‐μ‐chloro‐bis{[(2,3,4‐η)‐ethyl 6,6‐dimethyl‐5‐oxohept‐2‐enoato]palladium(II)}, [Pd2Cl2(C11H17O3)2], is a binuclear chloro‐bridged palladium allyl complex that was obtained serendipitously From the reaction of 6,6‐dimethyl‐2‐hepten‐4‐ynoate with Na2PdCl4 in water‐containing alcohol. The allyl group is substituted with an ester and a tert‐butylcarboxy group. The dimeric molecules link via C—H?O contacts into a two‐dimensional network parallel to the bc plane. 相似文献
4.
Jie Cheng Liang Xu Edwin D. Stevens Mark L. Trudell Sari Izenwasser Dean Wade 《Journal of heterocyclic chemistry》2004,41(4):569-574
Two conformationally constrained tropane derivatives were prepared as rigid nicotinic acetylcholine receptor ligands. A palladium catalyzed intramolecular α‐arylation reaction was employed to generate the tricyclic compounds in good yields from N‐(bromo‐chloropyridylmethyl)‐8‐azabicyclo[3.2.1]octan‐3‐ones. 相似文献
5.
A palladium‐catalyzed intramolecular α‐arylation of an amide in the presence of a bulky chiral N‐heterocyclic carbene ligand is the key step in the first catalytic synthesis of (3R)‐6‐chloro‐3‐(3‐chlorobenzyl)‐1,3‐dihydro‐3‐(3‐methoxyphenyl)‐2H‐indol‐2‐one ((R)‐ 5 ). This oxindole, in racemic form, had been shown previously to be an anticancer agent. (R)‐ 5 was obtained with an overall yield of 45% and with 96% enantioselectivity. 相似文献
6.
《化学:亚洲杂志》2017,12(18):2399-2403
An intramolecular exo ‐hydroarylation of 2‐aryloxy‐1,4‐disilylbut‐1‐en‐3‐ynes via ortho ‐C−H bond activation under palladium(0) and acid catalysis was found to give 2,3‐bis(silylmethylidene)‐2,3‐dihydrobenzofurans. The two silyl groups present probably promoted the reaction and played a key role in stabilizing the diene moiety in the product. The products readily led to functionalized condensed cycles by a Diels–Alder reaction. 相似文献
7.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(24):7093-7097
(E )‐δ‐Boryl‐substituted anti ‐homoallylic alcohols are synthesized in a highly diastereo‐ and enantioselective manner from 1,1‐di(boryl)alk‐3‐enes and aldehydes. Mechanistically, the reaction consists of 1) palladium‐catalyzed double‐bond transposition of the 1,1‐di(boryl)alk‐3‐enes to 1,1‐di(boryl)alk‐2‐enes, 2) chiral phosphoric acid catalyzed allylation of aldehydes, and 3) palladium‐catalyzed geometrical isomerization from the Z to E isomer. As a result, the configurations of two chiral centers and one double bond are all controlled with high selectivity in a single reaction vessel. 相似文献
8.
Can Liu Tao Miao Lei Zhang Prof. Pinhua Li Yicheng Zhang Prof. Lei Wang 《化学:亚洲杂志》2014,9(9):2584-2589
A novel and efficient palladium‐catalyzed C2 arylation of N‐substituted indoles with 1‐aryltriazenes for the synthesis of 2‐arylindoles was developed. In the presence of BF3 ? OEt2 and palladium(II) acetate (Pd(OAc)2), N‐substituted indoles reacted with 1‐aryltriazenes in N,N‐dimethylacetamide (DMAC) to afford the corresponding aryl–indole‐type products in good to excellent yields. 相似文献
9.
J. Gonzalo Rodríguez Jose Luis Tejedor 《Journal of polymer science. Part A, Polymer chemistry》2007,45(10):2038-2047
The monomer 5‐[(5‐ethynyl‐1‐naphthyl)ethynyl]‐N,N‐dimethylnaphthalen‐1‐amine was satisfactory obtained through the heterocoupling reaction of 5‐ethynyl‐N,N‐dimethylnaphthalen‐1‐amine and 4‐(5‐iodo‐1‐naphthyl)‐2‐methyl‐3‐butyn‐2‐ol catalyzed by a palladium–copper system, followed by acetone elimination. Poly{5‐[(5‐ethynyl‐1‐naphthyl)ethynyl]‐N,N‐dimethylnaphthalen‐1‐amine} was obtained through the reaction of the acetylene monomer with homogeneous rhodium and palladium catalyst complexes. The structure of the polymers always showed a trans–cisoidal chain configuration on the basis of IR and NMR spectra. Moreover, only for the rhodium catalyst complex in methanol was a dimeric product isolated in a very low yield, having a conjugated terminal ene–yne structure, which permitted the consideration of a metallated chain‐transfer intermediate in the polymer propagation. The mass determination of the polymers, by osmometry and gel permeation chromatography techniques, showed low average molecular weights. The kinetics of the catalyzed polymerization were analyzed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2038–2047, 2007 相似文献
10.
Eric E. Boros Istvan Kaldor Philip S. Turnbull 《Journal of heterocyclic chemistry》2011,48(3):733-736
2‐Methyl‐4‐(trifluoromethyl)‐1H‐indole‐5‐carbonitrile is a key intermediate in the synthesis of selective androgen receptor modulators discovered in these laboratories. A practical and convergent synthesis of the title compound starting from 4‐nitro‐3‐(trifluoromethyl)phenol and tert‐butyl acetoacetate was developed, including a telescoped procedure for synthesis (without isolation) and Nenitzescu reaction of 2‐trifluoromethyl‐1,4‐benzoquinone. Conversion of the known Nenitzescu indole product to a novel triflate intermediate followed by palladium‐catalyzed cyanation afforded a penultimate carbonitrile. Removal of the C‐3 tert‐butyl ester group on the indole through a decarboxylative pathway completed the synthesis of the title compound in six steps (27% overall yield) from 4‐nitro‐3‐(trifluoromethyl)phenol (five steps, 37% overall yield from tert‐butyl acetoacetate). J. Heterocyclic Chem., (2011). 相似文献
11.
In Kyu Moon Masuki Kawamoto Tatsuo Wada 《Journal of polymer science. Part A, Polymer chemistry》2009,47(9):2434-2442
In the present study, a new (E)‐rich‐enyne π‐conjugated polymer containing a carbazole was designed and synthesized. Two different synthesis methods of poly[N‐(2‐ethylhexyl)‐3,6‐carbazolyleneethynylene‐(E)‐vinylene] (PCZEV) have been prepared from 3,6‐diethynyl‐9(2‐ethylhexyl)carbazole by using the palladium‐carbene‐catalyzed reaction and/or by using the organolanthanide‐catalyzed reaction leading to well‐defined polymer, and their general properties were studied. Compared to poly[N‐(2‐ethylhexyl)‐3,6‐carbazolyleneethynylene] (PCE), the UV‐vis absorption and photoluminescence of the PCZEV was red‐shifted, which indicates the extension of conjugation length. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2434–2442, 2009 相似文献
12.
Palladium(II) Complexes of 1,1,3,3,5,5‐Hexakis(dimethylamino)‐λ5‐[1,3,5]triphosphinine 1,1,3,3,5,5‐Hexakis(dimethylamino)‐1λ5‐3λ5‐5λ5‐[1,3,5]triphosphinine ( 5 ) reacts with (benzonitrile)2PdCl2 to give the chelate complex dichloro(dodeca‐N‐methyl‐1λ5,3λ5,5λ5‐1,3,5‐triphosphinine‐1,1,3,3,5,5‐hexaamin‐C2,C4)palladium ( 6 ). In a pyridine‐d5 solution of 6 the complex dichloro(dodeca‐N‐methyl‐1λ5,3λ5,5λ5‐1,3,5‐triphosphinine‐1,1,3,3,5,5‐hexaamin‐C2)((2H5)pyridine‐N)palladium ( 7 ) is formed. The solute 7 could not be isolated as a solid, because elimination of the solvent regenerates 6 quantitatively. Properties, nmr and ir spectra of 6 and 7 are reported. 6 is characterized by the results of an X‐ray structural analysis. 相似文献
13.
A highly selective synthesis of 1‐substituted (E)‐buta‐1,3‐dienes with 4,4,5,5‐tetramethyl‐2‐vinyl‐1,3,2‐dioxaborolane as building block
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Justyna Szudkowska‐Frątczak Aline Ryba Adrian Franczyk Jędrzej Walkowiak Maciej Kubicki Piotr Pawluć 《应用有机金属化学》2014,28(3):137-139
Highly selective synthesis of 1‐substituted (E)‐buta‐1,3‐dienes via palladium‐catalyzed Suzuki–Miyaura cross‐coupling of (E)‐alkenyl iodides with 4,4,5,5‐tetramethyl‐2‐vinyl‐1,3,2‐dioxaborolane ( 1 ) is reported. The vinylboronate pinacol ester ( 1 ) acts as a vinyl building block to show high chemoselectivity for the Suzuki–Miyaura pathway versus Heck coupling in the presence of biphasic conditions (Pd(PPh3)4, aqueous K2CO3, toluene and ethanol). Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
14.
Palladium‐catalyzed carbonylative cyclization of β‐bromo‐α,β‐unsaturated carboxylic acids with 2,2‐dimethylhydrazine leading to 1‐(dimethylamino)‐1H‐pyrrole‐2,5‐diones
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β‐Bromo‐α,β‐unsaturated carboxylic acids are carbonylatively cyclized with 2,2‐dimethylhydrazine under carbon monoxide pressure in THF in the presence of a catalytic amount of a palladium catalyst along with a base to give 1‐(dimethylamino)‐1H‐pyrrole‐2,5‐diones. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
15.
J. Traeger A. Kelling U. Schilde H.‐J. Holdt 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(9):m238-m241
As an extension of recent findings on the recovery of palladium with dithioether extractants, single crystals of the chelating vicinal thioether sulfoxide ligand rac‐1‐[(2‐methoxyethyl)sulfanyl]‐2‐[(2‐methoxyethyl)sulfinyl]benzene, C12H18O3S2, (I), and its square‐planar dichloridopalladium complex, rac‐dichlorido{1‐[(2‐methoxyethyl)sulfanyl]‐2‐[(2‐methoxyethyl)sulfinyl]benzene‐κ2S,S′}palladium(II), [PdCl2(C12H18O3S2)], (II), have been synthesized and their structures analysed. The molecular structure of (II) is the first ever characterized involving a dihalogenide–PdII complex in which the palladium is bonded to both a thioether and a sulfoxide functional group. The structural and stereochemical characteristics of the ligand are compared with those of the analogous dithioether compound [Traeger et al. (2012). Eur. J. Inorg. Chem. pp. 2341–2352]. The sulfinyl O atom suppresses the electron‐pushing and mesomeric effect of the S—C...;C—S unit in ligand (I), resulting in bond lengths significantly different than in the dithioether reference compound. In contrast, in complex (II), those bond lengths are nearly the same as in the analogous dithioether complex. As observed previously, there is an interaction between the central PdII atom and the O atom that is situated above the plane. 相似文献
16.
Alok K. Mukherjee Subhadra Guha M. Wahab Khan Nitya G. Kundu Madeleine Helliwell 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(1):85-87
Two isoindolin‐1‐one derivatives, (Z)‐3‐benzylidene‐N‐phenylisoindolin‐1‐one, C21H15NO, (II), and (Z)‐3‐benzylidene‐N‐(4‐methoxyphenyl)isoindolin‐1‐one, C22H17NO2, (III), were synthesized by the palladium‐catalysed heteroannulation. The molecules of both compounds have a Z configuration. The interplanar angles between the five‐ and six‐membered rings of the isoindolinone moiety in (II) and (III) are 1.66 (11) and 2.26 (7)°, respectively. The phenyl rings at the N‐position in (II) and (III) are twisted out of the C4N ring plane by 62.77 (11) and 67.10 (7)°, respectively. The substitutions at the N and C‐3 positions of the isoindolinone system have little influence on the molecular dimensions of the resulting compounds. 相似文献
17.
Chiral Palladacycle Catalysts Generated on a Single‐Handed Helical Polymer Skeleton for Asymmetric Arylative Ring Opening of 1,4‐Epoxy‐1,4‐dihydronaphthalene
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Dr. Takeshi Yamamoto Yuto Akai Prof. Dr. Michinori Suginome 《Angewandte Chemie (International ed. in English)》2014,53(47):12785-12788
Post‐polymerization C? H activation of poly(quinoxaline‐2,3‐diyl)‐based helically chiral phosphine ligands (PQXphos) with palladium(II) acetate afforded chiral phosphapalladacycles quantitatively. In situ generated palladacycles exhibited enantioselectivities up to 94 % ee in the palladium‐catalyzed asymmetric ring‐opening arylation of 1,4‐epoxy‐1,4‐dihydronaphthalenes with arylboronic acids. 相似文献
18.
J. Gonzalo Rodríguez Antonio Lafuente Javier Arranz 《Journal of polymer science. Part A, Polymer chemistry》2005,43(24):6438-6444
The synthesis and polymerization of (E)‐p‐[(p‐methoxyphenyl)‐2‐ethenyl]phenylacetylene was carried out with a homogeneous vanadium acetylacetonate/aluminum triethyl catalyst system, a bis(rhodium chloride cycloocta‐1,5‐diene) complex, and a palladium/trimethylsilyl complex. In all cases, the main fraction was a polymer with a stereoregular structure. The polymerization with the vanadium catalyst gave a polymer fraction in a low yield. The polymerization of (E)‐p‐[(p‐methoxyphenyl)‐2‐ethenyl]phenylacetylene with the soluble rhodium complex gave a polymer in a high yield. The soluble palladium/chlorotrimethylsilane complex gave a polymer in a good yield. On the basis of the spectroscopic data, the poly{(E)‐p‐[(p‐methoxyphenyl)‐2‐ethenyl]phenylacetylene)} obtained, in all cases, showed a cis–transoidal stereoregular structure. The molecular mass of poly{(E)‐p‐[(p‐methoxyphenyl)‐2‐ethenyl]phenylacetylene)} was determined by the matrix‐assisted laser desorption/ionization time‐of‐flight technique. The kinetics of the reaction were analyzed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6438–6444, 2005 相似文献
19.
Allison M. Mills Martin Lutz Gino P. F. Van Strijdonck Paul C. J. Kamer Piet W. N. M. Van Leeuwen Anthony L. Spek 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(12):m583-m585
The palladium(II) centre in the title compound, [PdCl2(C21H18N2OS)], is coordinated to the pyridyl N atom and to the thiazolidinone S atom of the 5‐benzyl‐3‐phenyl‐2‐(2‐pyridyl)thiazolidin‐4‐one ligand, resulting in a five‐membered chelate ring. Two cis‐chloro ligands complete the square‐planar coordination environment of the metal. Although the geometry at the Pd centre is essentially planar, the N—Pd—S bite angle of 85.20 (8)° causes deviations in the cis angles from the ideal value of 90°. Opposite enantiomers form one‐dimensional chains in the cell via a short S?O intermolecular interaction. 相似文献
20.
Dr. Hai‐Tao Zhu Li‐Jing Wang Dr. Ke‐Gong Ji Prof. Dr. Xue‐Yuan Liu Prof. Dr. Yong‐Min Liang 《化学:亚洲杂志》2012,7(8):1862-1866
Functionalized 3,4‐dihalogenated furan‐2(5 H)‐ones can be readily prepared in moderate to good yields by treating 4‐hydroxy‐4‐arylbut‐2‐ynoate derivatives with ICl, IBr, and I2. Both halogen atoms of the electrophile are incorporated in the product. The resulting halides can further afford polycyclic aromatic compounds using known palladium‐catalyzed coupling reactions. 相似文献