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1.
An α‐diimine Pd(II) complex containing chiral sec‐phenethyl groups, {bis[N,N′‐(4‐methyl‐2‐sec‐phenethylphenyl)imino]‐2,3‐butadiene}dichloropalladium (rac‐ C1 ), was synthesized and characterized. rac‐ C1 was applied as an efficient catalyst for the Suzuki–Miyaura cross‐coupling reaction between various aniline halides and arylboronic acid in PEG‐400–H2O at room temperature. Among a series of aniline halides, rac‐ C1 did not catalyze the cross‐coupling of aniline chlorides and fluorides but efficiently catalyzed the cross‐coupling of aniline bromides and iodides with phenylboronic acid. The catalytic activity reduced slightly with increasing steric hindrance of the aniline bromides. The complexes {bis[N,N′‐(4‐fluoro‐2,6‐diphenylphenyl)imino]‐2,3‐butadiene}dichloropalladium and {bis[N,N′‐(4‐fluoro‐2,6‐diphenylphenyl)imino]acenaphthene}dichloropalladium were also found to be efficient catalysts for the reaction. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
2.
Viktor A. Tafeenko Aleksander N. Nikolaev Rene Peschar Olga V. Kaukova Henk Schenk Leonid A. Aslanov 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(4):o297-o299
The crystal structure of the title compound, C6H8N+·C8HN4O2−, is characterized by three independent ion pairs (A, B and C) in the asymmetric unit. Each ion pair consists of an anion and a cation, and the three ion pairs have similar geometric parameters. All the anions are arranged as dianion dimers via two N—H⋯O hydrogen bonds and the dimers form one‐dimensional columns parallel to the b axis as a result of π–π interactions. The cations are also stacked, in two different ways: one type of stacking consists of alternating A and B cations, while the other type consists of C cations only. Each dianion dimer stack is surrounded by eight stacks of cations and is not connected directly to other dianion stacks. 相似文献
3.
Mao‐Lin Hu Xiao‐Qing Cai Qian Shi Ya‐Qian Cheng 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(11):m575-m577
In the polymeric title compound, [Cu(im)Cl(phen)]n, where im is the imidazolate anion (C3H3N2) and phen is 1,10‐phenanthroline (C12H8N2), each CuII ion is five‐coordinated by four basal N atoms (two from two different im anions and two from one phen ligand) and one axial Cl atom, in a distorted square‐pyramidal coordination geometry. Moreover, each im anion bridges two identical {CuCl(phen)}+ cations through its two N atoms, resulting in a one‐dimensional zigzag chain along the crystallographic a axis. In addition, pairs of adjacent chains are staggered by π–π interactions, generating a two‐dimensional layer, and neighbouring layers are further linked by two different kinds of C—H⋯Cl interactions, producing a three‐dimensional network. 相似文献
4.
Gene‐Hsiang Lee 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(5):o241-o244
The molecule of N,N′‐bis(4‐pyridylmethyl)oxalamide, C14H14N4O2, (I) or 4py‐ox, has an inversion center in the middle of the oxalamide group. Adjacent molecules are then linked through intermolecular N—H...N and C—H...O hydrogen bonds, forming an extended supramolecular network. 4,4′‐{[Oxalylbis(azanediyl)]dimethylene}dipyridinium dinitrate, C14H16N4O22+·2NO3−, (II), contains a diprotonated 4py‐ox cation and two nitrate counter‐anions. Each nitrate ion is hydrogen bonded to four 4py‐ox cations via intermolecular N—H...O and C—H...O interactions. Adjacent 4py‐ox cations are linked through weak C—H...O hydrogen bonding between an α‐pyridinium C atom and an oxalamide O atom, forming a two‐dimensional extended supramolecular network. 相似文献
5.
Lithiation of N‐(2,6‐diisopropylphenyl)‐N′‐(2‐pyridylethyl)benzamidine ( 1 ) with LiN(SiMe3)2 in a solvent mixture of toluene and TMEDA yields hexameric lithium N‐(2,6‐diisopropylphenyl)‐N′‐(2‐pyridylethyl)benzamidinate ( 2 ), which can be purified by recrystallization from a solvent mixture of toluene and THF. The three‐coordinate lithium ions have T‐shaped coordination spheres. The negative charge is delocalized within the 1,3‐diazaallylic system, which adopts a (syn‐Z)‐arrangement. 相似文献
6.
Gerhard Baum Alexander J. Blake Dieter Fenske Peter Hubberstey Carine Julio Matthew A. Withersby 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):m542-m544
Molecules of the title compound, [Cu(C2H3N)(C11H9N5)(C6H6N2O)](BF4)2·2C2H3N, comprise (acetonitrile)[2,6‐bis(pyrazol‐1‐yl)pyridine](isonicotinamide)copper(II) cations, tetrafluoroborate anions and lattice acetonitrile molecules. The cations have distorted square‐pyramidal geometries in which the N3‐donor, viz. 2,6‐bis(pyrazol‐1‐yl)pyridine, and the N‐donor, viz. the isonicotinamide ligand, occupy the four basal positions, with the coordinated acetonitrile N‐donor atom occupying the apical position. Pairs of cations are linked by N—H?F hydrogen bonds through tetrafluoroborate anions, forming centrosymmetric dimers, which are further linked by C—H?O hydrogen bonds into two‐dimensional undulating sheets, three of which interpenetrate to generate a two‐dimensional network. 相似文献
7.
Dr. Tetsuo Sato Yoichi Hirose Daisuke Yoshioka Tsubasa Shimojo Prof. Dr. Shuichi Oi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(46):15710-15718
The synthesis and characterisation of a series of new Rh and Au complexes bearing 1,2,4‐triazol‐3‐ylidenes with a N‐2,4‐dinitrophenyl (N‐DNP) substituent are described. IR, NMR, single‐crystal X‐ray diffraction and computational analyses of the Rh complexes revealed that the N‐heterocyclic carbenes (NHCs) behaved as strong π acceptors and weak σ donors. In particular, a natural bond orbital (NBO) analysis revealed that the contributions of the Rh→Ccarbene π backbonding interaction energies (ΔEbb) to the bond dissociation energies (BDE) of the Rh? Ccarbene bond for [RhCl(NHC)(cod)] (cod=1,5‐cyclooctadiene) reached up to 63 %. The Au complex exhibited superior catalytic activity in the intermolecular hydroalkoxylation of cyclohexene with 2‐methoxyethanol. The NBO analysis suggested that the high catalytic activity of the AuI complex resulted from the enhanced π acidity of the Au atom. 相似文献
8.
Su‐Ping Zhou Xu‐Xian Wu Chao Zu Zi‐Lu Chen Fu‐Pei Liang 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(2):m26-m28
The PbII cation in the title compound, [Pb2(C14H4N2O8)]n, is seven‐coordinated by one N atom and six O atoms from four 4,4′‐bipyridine‐2,2′,6,6′‐tetracarboxylate (BPTCA4−) ligands. The geometric centre of the BPTCA4− anion lies on an inversion centre. Each pyridine‐2,6‐dicarboxylate moiety of the BPTCA4− ligand links four PbII cations via its pyridyl N atom and two carboxylate groups to form two‐dimensional sheets. The centrosymmetric BPTCA4− ligand then acts as a linker between the sheets, which results in a three‐dimensional metal–organic framework. 相似文献
9.
Xiao‐Wen Li Yan‐Tuan Li Zhi‐Yong Wu Fu‐Bin Jiang 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(8):m218-m221
The title complex, [Cu4(C11H10N3O4)2(C6H6N4S2)2](C6H2N3O7)2, consists of a circular tetracopper(II) cation with an embedded inversion centre and two uncoordinated picrate (2,4,6‐trinitrophenolate) anions. The CuII cations at the inner sites of N‐(2‐aminoethyl)‐N′‐(2‐carboxylatophenyl)oxamidate(3−) (oxbe) have square‐planar environments and those at the outer sites are in square‐pyramidal geometries. The separations of pairs of CuII cations bridged by cis‐oxamide and carboxylate groups are 5.2217 (5) and 5.2871 (5) Å, respectively. The tetracopper(II) cations and picrate anions are connected by N—H...O hydrogen bonds into a two‐dimensional network parallel to the (010) plane, and these two‐dimensional networks are assembled by two types of π–π stacking interactions into a three‐dimensional supramolecular structure. 相似文献
10.
Valeska Gerhardt Maya Tutughamiarso Michael Bolte 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(5):o179-o187
The derivatives of pyrimidin‐4‐one can adopt either a 1H‐ or a 3H‐tautomeric form, which affects the hydrogen‐bonding interactions in cocrystals with compounds containing complementary functional groups. In order to study their tautomeric preferences, we crystallized 2,6‐diaminopyrimidin‐4‐one and 2‐amino‐6‐methylpyrimidin‐4‐one. During various crystallization attempts, four structures of 2,6‐diaminopyrimidin‐4‐one were obtained, namely solvent‐free 2,6‐diaminopyrimidin‐4‐one, C4H6N4O, (I), 2,6‐diaminopyrimidin‐4‐one–dimethylformamide–water (3/4/1), C4H6N4O·1.33C3H7NO·0.33H2O, (Ia), 2,6‐diaminopyrimidin‐4‐one dimethylacetamide monosolvate, C4H6N4O·C4H9NO, (Ib), and 2,6‐diaminopyrimidin‐4‐one–N‐methylpyrrolidin‐2‐one (3/2), C4H6N4O·1.5C5H9NO, (Ic). The 2,6‐diaminopyrimidin‐4‐one molecules exist only as 3H‐tautomers. They form ribbons characterized by R22(8) hydrogen‐bonding interactions, which are further connected to form three‐dimensional networks. An intermolecular N—H...N interaction between amine groups is observed only in (I). This might be the reason for the pyramidalization of the amine group. Crystallization experiments on 2‐amino‐6‐methylpyrimidin‐4‐one yielded two isostructural pseudopolymorphs, namely 2‐amino‐6‐methylpyrimidin‐4(3H)‐one–2‐amino‐6‐methylpyrimidin‐4(1H)‐one–dimethylacetamide (1/1/1), C5H7N3O·C5H7N3O·C4H9NO, (IIa), and 2‐amino‐6‐methylpyrimidin‐4(3H)‐one–2‐amino‐6‐methylpyrimidin‐4(1H)‐one–N‐methylpyrrolidin‐2‐one (1/1/1), C5H7N3O·C5H7N3O·C5H9NO, (IIb). In both structures, a 1:1 mixture of 1H‐ and 3H‐tautomers is present, which are linked by three hydrogen bonds similar to a Watson–Crick C–G base pair. 相似文献
11.
Agata Biaoska Zbigniew Ciunik 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(4):o182-o185
Comparison of the structures of strychninium N‐phthaloyl‐β‐alaninate N‐phthaloyl‐β‐alanine, C21H23N2O2+·C11H8NO4−·C11H9NO4, and brucinium N‐phthaloyl‐β‐alaninate 5.67‐hydrate, C23H27N2O4+·C11H8NO4−·5.67H2O, reveals that, unlike strychninium cations, brucinium cations display a tendency to produce stacking interactions with cocrystallizing guests. 相似文献
12.
An efficient method has been developed for one-pot three-component coupling reactions of various aldehydes, 1-cyclohexen-2-one, and primary or secondary amines in the presence of a catalytic amount of Yb(OTf)3 under mild conditions to afford the corresponding 2-arylmethyl N-substituted anilines in good yields. In addition, the catalyst was easily recovered and could be reused for at least four cycles without any loss of activity. 相似文献
13.
Adam Neuba Enver Akin Sonja Herres‐Pawlis Ulrich Flrke Gerald Henkel 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(5):m194-m197
The title compounds, namely 2,6‐bis[(1,3‐dimethylimidazolin‐2‐ylidene)amino]pyridinium perchlorate, C15H24N7+·ClO4−, (I), and bis{2,6‐bis[(1,3‐dimethylimidazolin‐2‐ylidene)amino]pyridinium} μ‐oxido‐bis[trichloridoiron(III)], (C15H24N7)2[Fe2Cl6O], (II), are structurally unusual examples of the organization of molecular units via base pairing. The cations in salts (I) and (II) are derived from the bisguanidine N2,N6‐bis(1,3‐dimethylimidazolin‐2‐ylidene)pyridine‐2,6‐diamine, which associates in centrosymmetric pairs via two N—H...N hydrogen‐bond interactions. N—H...N bridges are formed between the protonated pyridine N atom and one of the nonprotonated guanidine N atoms, with N...H distances of 2.01 (1)–2.10 (1) Å. Compound (I) contains two crystallographically independent cations and anions per asymmetric unit. One of the perchlorate anions is disordered, while the [Fe2Cl6O]2− anion lies on an inversion centre. 相似文献
14.
In the title compound, {[Zn(C19H17N5O2)2(H2O)2](NO3)2}n, the ZnII cation is located at an inversion centre within a slightly distorted octahedron, ligated by four N atoms from four N2,N6‐bis[(pyridin‐3‐yl)methyl]pyridine‐2,6‐dicarboxamide (L) ligands occupying a plane about the ZnII atom with the two water O atoms perpendicular to that. In the complex molecule, the bidentate bridging L ligands display helical R and S conformers, and link the ZnII cations into a one‐dimensional centrosymmetric double‐chain structure containing 32‐membered rings. The nitrate anions reside in these rings and are involved in multiple N—H...O hydrogen‐bond interactions. On excitation at 390 nm, the title compound displays a strong blue emission centred at 449 nm. Investigation of the thermal stability shows that the network structure is stable up to 420 K. 相似文献
15.
Randi Zhang Yanping Ma Mingyang Han Gregory A. Solan Yaqing Pi Yang Sun Wen‐Hua Sun 《应用有机金属化学》2019,33(10)
The bis(arylimino)pyridines, 2‐[CMeN{2,6‐{(4‐FC6H4)2CH}2–4‐NO2}]‐6‐(CMeNAr)C5H3N (Ar = 2,6‐Me2C6H3 L1 , 2,6‐Et2C6H3 L2 , 2,6‐i‐Pr2C6H3 L3 , 2,4,6‐Me3C6H2 L4 , 2,6‐Et2–4‐MeC6H2 L5 ), each containing one N′‐2,6‐bis{di(4‐fluorophenyl)methyl}‐4‐nitrophenyl group, have been synthesized by two successive condensation reactions from 2,6‐diacetylpyridine. Their subsequent treatment with anhydrous cobalt (II) chloride gave the corresponding N,N,N′‐CoCl2 chelates, Co1 – Co5 , in excellent yield. All five complexes have been characterized by 1H/19F NMR and IR spectroscopy as well as by elemental analysis. In addition, the molecular structures of Co1 and Co3 have been determined and help to emphasize the differences in steric properties imposed by the inequivalent N‐aryl groups; distorted square pyramidal geometries are adopted by each complex. Upon activation with either methylaluminoxane (MAO) or modified methylaluminoxane (MMAO), precatalyts Co1 – Co5 collectively exhibited very high activities for ethylene polymerization with 2,6‐dimethyl‐substituted Co1 the most active (up to 1.1 × 107 g (PE) mol?1 (Co) h?1); the MAO systems were generally more productive. Linear polyethylenes of exceptionally high molecular weight (Mw up to 1.3 × 106 g mol?1) were obtained in all cases with the range in dispersities exhibited using MAO as co‐catalyst noticeably narrower than with MMAO [Mw/Mn: 3.55–4.77 ( Co1 – Co5 /MAO) vs. 2.85–12.85 ( Co1 – Co5 /MMAO)]. Significantly, the molecular weights of the polymers generated using this class of cobalt catalyst are higher than any literature values reported to date using related N,N,N‐bis (arylimino)pyridine‐cobalt catalysts. 相似文献
16.
Xin‐Qiang Wang Wen‐Tao Yu Dong Xu Guang‐Hui Zhang Yan‐Ling Geng 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):m278-m280
The title complex, [MnHg(NCS)4(C2H5NO)2]n, consists of slightly distorted MnN4O2 octahedra and HgS4 tetrahedra. Each MnII cation is bound to four N atoms of the NCS groups and two O atoms of the N‐methylformamide (NMF) ligands in a cis configuration. Each HgII cation is coordinated to four S atoms of NCS groups. Each pair of MnII and HgII cations is connected by an –NCS– bridge, forming an infinite three‐dimensional –Mn—NCS—Hg– network. 相似文献
17.
Expanded‐Ring N‐Heterocyclic Carbenes Efficiently Stabilize Gold(I) Cations,Leading to High Activity in π‐Acid‐Catalyzed Cyclizations 下载免费PDF全文
Oleg S. Morozov Andrey V. Lunchev Alexander A. Bush Aleksandr A. Tukov Andrey F. Asachenko Victor N. Khrustalev Sergey S. Zalesskiy Valentine P. Ananikov Mikhail S. Nechaev 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(20):6162-6170
A series of six‐ and seven‐membered expanded‐ring N‐heterocyclic carbene (er‐NHC) gold(I) complexes has been synthesized using different synthetic approaches. Complexes with weakly coordinating anions [(er‐NHC)AuX] (X?=BF4?, NTf2?, OTf?) were generated in solution. According to their 13C NMR spectra, the ionic character of the complexes increases in the order X?=Cl?<NTf2?<OTf?<BF4?. Additional factors for stabilization of the cationic complexes are expansion of the NHC ring and the attachment of bulky substituents at the nitrogen atoms. These er‐NHCs are bulkier ligands and stronger electron donors than conventional NHCs as well as phosphines and sulfides and provide more stabilization of [(L)Au+] cations. A comparative study has been carried out of the catalytic activities of five‐, six‐, and seven‐membered carbene complexes [(NHC)AuX], [(Ph3P)AuX], [(Me2S)AuX], and inorganic compounds of gold in model reactions of indole and benzofuran synthesis. It was found that increased ionic character of the complexes was correlated with increased catalytic activity in the cyclization reactions. As a result, we developed an unprecedentedly active monoligand cationic [(THD‐Dipp)Au]BF4 (1,3‐bis(2,6‐diisopropylphenyl)‐3,4,5,6‐tetrahydrodiazepin‐2‐ylidene gold(I) tetrafluoroborate) catalyst bearing seven‐membered‐ring carbene and bulky Dipp substituents. Quantitative yields of cyclized products were attained in several minutes at room temperature at 1 mol % catalyst loadings. The experimental observations were rationalized and fully supported by DFT calculations. 相似文献
18.
Zhong‐Lu You Hai‐Liang Zhu 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(11):m567-m568
The title complex, [Ag2(C7H5O2)2(C18H18F2N2)]n, is a dinuclear silver(I) compound with one inversion centre between pairs of Ag atoms and another at the mid‐point of the central C—C bond in the butane‐1,4‐diamine moiety. Each of the smallest repeat units consists of two silver(I) cations, two benzoate anions and one N,N′‐bis(2‐fluorobenzylidene)butane‐1,4‐diamine Schiff base ligand. Each AgI ion is three‐coordinated in a trigonal configuration by two O atoms from two benzoate anions and one N atom from a Schiff base ligand. The di‐μ‐benzoato‐disilver(I) moieties are linked by the bridging Schiff base ligand, giving zigzag polymeric chains with an [–Ag⋯Ag—N—C—C—C—C—N–]n backbone running along the b axis. 相似文献
19.
Ana María Atria Maria Teresa Garland Ricardo Baggio 《Acta Crystallographica. Section C, Structural Chemistry》2010,66(11):o547-o552
Two structures presenting an uncomplexed 2,6‐diaminopurine (dap) group are reported, namely 2,6‐diamino‐9H‐purine monohydrate, C5H6N6·H2O, (I), and bis(2,6‐diamino‐9H‐purin‐1‐ium) 2‐(2‐carboxylatophenyl)acetate heptahydrate, 2C5H7N6+·C9H6O42−·7H2O, (II). Both structures are rather featureless from a molecular point of view, but present instead an outstanding hydrogen‐bonding scheme. In compound (I), this is achieved through a rather simple independent unit content (one neutral dap and one water molecule) and takes the form of two‐dimensional layers tightly connected by strong hydrogen bonds, and interlinked by much weaker hydrogen bonds and π–π interactions. In compound (II), the fundamental building blocks are more complex, consisting of two independent 2,6‐diamino‐9H‐purin‐1‐ium (Hdap+) cations, one homophthalate [2‐(2‐carboxylatophenyl)acetate] dianion and seven solvent water molecules. The large number of hydrogen‐bond donors and acceptors produces 26 independent interactions, leading to an extended and complicated network of hydrogen bonds in a packing organization characterized by the stacking of interleaved anionic and cationic planar arrays. These structural characteristics are compared with those of similar compounds in the literature. 相似文献
20.
Jan Janczak Mayura M. M. Rubinger Leandro C. Alves Marcelo R. L. Oliveira 《Acta Crystallographica. Section C, Structural Chemistry》2012,68(11):m312-m316
The rigid organic linkers N‐(4‐bromophenylsulfonyl)dithiocarbimate(2−) and N‐(4‐iodophenylsulfonyl)dithiocarbimate(2−) crystallize with two potassium cations and two water molecules in their asymmetric units, forming the title coordination polymers, [K2(C7H4BrNO2S3)(H2O)2]n and [K2(C7H4INO2S3)(H2O)2]n. The anions and the water molecules link the potassium cations into broad two‐dimensional networks, which are further linked by K...halide interactions. 相似文献