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1.
Structural Analysis and Inclusion Mechanism of Native and Permethylated α‐Cyclodextrin‐Based Rotaxanes Containing Alkylene Axles 下载免费PDF全文
Yosuke Akae Dr. Yasuhito Koyama Dr. Hiromitsu Sogawa Dr. Yoshihiro Hayashi Prof. Susumu Kawauchi Prof. Shigeki Kuwata Prof. Toshikazu Takata 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(15):5335-5341
Native α‐cyclodextrin‐ (α‐CD) and permethylated α‐CD (PMeCD)‐based rotaxanes with various short alkylene chains as axles can be synthesized through a urea end‐capping method. Native α‐CD tends to form [3]‐ or [5]pseudorotaxanes and not [2]‐ or [4]pseudorotaxanes, which indicates that the coupled CDs act as a single fragment. End‐capping reactions of the pseudorotaxanes with C18 and C24 axle lengths do not occur because the axle termini are covered by the densely stacked CDs. The number of PMeCDs on the pseudorotaxane is flexible and mainly depends on the axle length. Peracetylated α‐CD (PAcCD)‐based rotaxanes are synthesized through O‐acetylation of the α‐CD‐based rotaxanes without any decomposition of the rotaxanated structures. The structures of PMeCD‐based [3]‐ and [4]rotaxanes, and the molecular dynamics calculations on [3]pseudorotaxanes, indicate that the tail face of PMeCDs is regularly directed toward the axle termini. On the basis of the results obtained, it can be concluded that the directions and numbers of CDs in rotaxanes containing short alkylene chains depend on 1) the interactions between CDs, 2) the length of the alkylene axle, and 3) the interactions between the axle end and tail face of the CD. 相似文献
2.
A novel [2]pseudorotaxane of cucurbit[6]uril(CB[6]) and 1‐butyl‐3‐methyl‐imidazolium bromide ([C4mim]Br) was synthesized by directly mixing the host and the guest molecules in non‐aqueous system. Structural characterizations of the [2]pseudorotaxane were carried out by 1D, 2D NMR and X‐ray crystallography techniques both in solution and in crystal structure. The crystal structure demonstrated that CB[6] and [C4mim]Br formed a complex with the ratio 1:1, in which one guest [C4mim]Br was included inside the CB[6], while two other [C4mim]Br molecules were free and surrounded the [2]pseudorotaxane as solvent molecules, which could stabilize the crystal structure through hydrogen bonds. Moreover, parallel solvent channels consisting by free [C4mim]Br molecules occupied the pores among the frame of the pseudorotaxanes and formed zigzag lines in the crystal structure. [C4mim]Br can serve as not only the guest reactant but also the solvent in the formation of [2]pseudorotaxane formation. 相似文献
3.
α‐Halogenoacetanilides as Hydrogen‐Bonding Organocatalysts that Activate Carbonyl Bonds: Fluorine versus Chlorine and Bromine 下载免费PDF全文
Dr. Sylvain Koeller Dr. Coralie Thomas Dr. Fréderic Peruch Dr. Alain Deffieux Dr. Stéphane Massip Prof. Dr. Jean‐Michel Léger Dr. Jean‐Pierre Desvergne Prof. Dr. Anne Milet Dr. Brigitte Bibal 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(10):2849-2859
α‐Halogenoacetanilides (X=F, Cl, Br) were examined as H‐bonding organocatalysts designed for the double activation of C?O bonds through NH and CH donor groups. Depending on the halide substituents, the double H‐bond involved a nonconventional C?H???O interaction with either a H?CXn (n=1–2, X=Cl, Br) or a H?CAr bond (X=F), as shown in the solid‐state crystal structures and by molecular modeling. In addition, the catalytic properties of α‐halogenoacetanilides were evaluated in the ring‐opening polymerization of lactide, in the presence of a tertiary amine as cocatalyst. The α‐dichloro‐ and α‐dibromoacetanilides containing electron‐deficient aromatic groups afforded the most attractive double H‐bonding properties towards C?O bonds, with a N?H???O???H?CX2 interaction. 相似文献
4.
[3]Pseudorotaxanes [ 1 (α‐CD)2][X] (X=Cl, NO3), prepared from reaction of an N‐alkylbipyridinium [4,4′‐bpy‐N‐(CH2)10OC6H3‐3,5‐(OMe)2][X] ([ 1 ][X]) and α‐CD, react with M(NO3)2(en) (M=Pd, Pt; en=1,2‐ethylenediamine) in a 2:1 molar ratio to afford [5]rotaxanes [M{(4,4′‐bpy‐N‐(CH2)10OC6H3‐3,5‐(OMe)2)(α‐CD)2}2 (en)][NO3]4 ([ 2 (α‐CD)4][NO3]4, M=Pd; [ 3 (α‐CD)4][NO3]4, M=Pt). A similar reaction of [ 1 ][Cl] with [M(NO3)2(en)] (M=Pd, Pt) produces amphiphilic Pd and Pt complexes, [ 2 ][NO3]4 and [ 3 ][NO3]4. Complexes [ 2 ][NO3]4 and [ 3 ][NO3]4 form micelles in the presence of small amounts of dyes (Nile red and pyrene) in water. The critical micelle concentration (CMC) was determined by the absorption peak of the dye, which is encapsulated in the micelles in solution. Micelle formation is confirmed by dynamic light scattering measurement of the solution and TEM (transmission electron microscopy) images of the micelles deposited from the solution. Addition of α‐CD to the aqueous solution containing these amphiphilic complexes results in degradation of the micelle structure and the formation of [5]rotaxanes, [ 2 (α‐CD)4][NO3]4 and [ 3 (α‐CD)4][NO3]4. 相似文献
5.
Xuzhuo Sun Bo Li Jin Cao Jing Chen Ning Wang Dongjin Wan Haibo Zhang Xiaohai Zhou 《中国化学》2012,30(4):941-946
A pseudorotaxane of cucurbit[6]uril (CB[6]) with guest molecule N,N′‐hexamethylenebis (pyrazinyl perchlorate) (BPHP) was synthesized and characterized by 1H NMR spectra, IR, single crystal X‐ray diffraction analysis and thermogravimetric analysis. The structure of the pseudorotaxane (CB[6]·BPHP) is stabilized by host‐guest hydrogen bonds. Self‐assembly of the pseudorotaxane produces infinite one‐dimensional and two‐dimensional networks with intermolecular hydrogen bonds. In the molecular packing of the CB[6]·BPHP, ClO4?(H2O)2 water clusters serve as bridges to associate these pseudorotaxanes and form three‐dimensional networked pseudopolyrotaxane. 相似文献
6.
Probing the reactivity of microhydrated α‐nucleophile in the anionic gas‐phase SN2 reaction 下载免费PDF全文
Wen‐Yang Zhao Jie Yu Si‐Jia Ren Xi‐Guang Wei Fang‐Zhou Qiu Peng‐Hui Li He Li Yi‐Peng Zhou Chang‐Zhen Yin An‐Pu Chen Hao Li Lei Zhang Jun Zhu Yi Ren Kai‐Chung Lau 《Journal of computational chemistry》2015,36(11):844-852
To probe the kinetic performance of microsolvated α‐nucleophile, the G2(+)M calculations were carried out for the gas‐phase SN2 reactions of monohydrated and dihydrated α‐oxy‐nucleophiles XO?(H2O)n = 1,2 (X = HO, CH3O, F, Cl, Br), and α‐sulfur‐nucleophile, HSS?(H2O)n = 1,2, toward CH3Cl. We compared the reactivities of hydrated α‐nucleophiles to those of hydrated normal nucleophiles. Our calculations show that the α‐effect of monohydrated and dihydrated α‐oxy‐nucleophiles will become weaker than those of unhydrated ones if we apply a plot of activation barrier as a function of anion basicity. Whereas the enhanced reactivity of monohydrated and dihydrated ROO? (R = H, Me) could be observed if compared them with the specific normal nucleophiles, RO? (R = H, Me). This phenomena can not be seen in the comparisons of XO?(H2O)n = 1,2 (X = F, Cl, Br) with ClC2H4O?(H2O)n = 1,2, a normal nucleophile with similar gas basicity to XO?(H2O)n = 1,2. These results have been carefully analyzed by natural bond orbital theory and activation strain model. Meanwhile, the relationships between activation barriers with reaction energies and the ionization energies of α‐nucleophile are also discussed. © 2015 Wiley Periodicals, Inc. 相似文献
7.
Dr. Jingshun Zhang Zhiqiang Hao Dr. Wei Gao Lan Xin Lei Zhang Prof. Ying Mu 《化学:亚洲杂志》2013,8(9):2079-2087
A series of NCO/NCS pincer precursors, 3‐(Ar2OCH2)‐2‐Br‐(Ar1N?CH)C6H3 ((Ar1NCOAr2)Br, 3a , 3b , 3c , 3d ) and 3‐(2,6‐Me2C6H3SCH2)‐2‐Br‐(Ar1N?CH)C6H3 ((Ar1NCSMe)Br, 4a and 4b ) were synthesized and characterized. The reactions of [Ar1NCOAr2]Br/ [Ar1NCSMe]Br with nBuLi and the subsequent addition of the rare‐earth‐metal chlorides afforded their corresponding rare‐earth‐metal–pincer complexes, that is, [(Ar1NCOAr2)YCl2(thf)2] ( 5a , 5b , 5c , 5d ), [(Ar1NCOAr2)LuCl2(thf)2] ( 6a , 6d ), [(Ar1NCOAr2)GdCl2(thf)2] ( 7 ), [{(Ar1NCSMe)Y(μ‐Cl)}2{(μ‐Cl)Li(thf)2(μ‐Cl)}2] ( 8 , 9 ), and [{(Ar1NCSMe)Gd(μ‐Cl)}2{(μ‐Cl)Li(thf)2(μ‐Cl)}2] ( 10 , 11 ). These diamagnetic complexes were characterized by 1H and 13C NMR spectroscopy and the molecular structures of compounds 5a , 6a , 7 , and 10 were well‐established by X‐ray diffraction analysis. In compounds 5a , 6a , and 7 , all of the metal centers adopted distorted pentagonal bipyramidal geometries with the NCO donors and two oxygen atoms from the coordinated THF molecules in equatorial positions and the two chlorine atoms in apical positions. Complex 10 is a dimer in which the two equal moieties are linked by two chlorine atoms and two Cl? Li? Cl bridges. In each part, the gadolinium atom adopts a distorted pentagonal bipyramidal geometry. Activated with alkylaluminum and borate, the gadolinium and yttrium complexes showed various activities towards the polymerization of isoprene, thereby affording highly cis‐1,4‐selective polyisoprene, whilst the NCO? lutetium complexes were inert under the same conditions. 相似文献
8.
Anion‐ and Solvent‐Induced Assembly and Reversible Structural Transformation of d10‐Metal Coordination Architectures Containing N‐(4‐(4‐Aminophenyloxy)phenyl)isonicotinamide 下载免费PDF全文
Prof. Biing‐Chiau Tzeng Yu‐Ching Hung Dr. Gene‐Hsiang Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1522-1530
We set out studies on anion‐ and solvent‐induced assembly based on the ligand N‐(4‐(4‐aminophenyloxy)phenyl)isonicotinamide (papoa), which is synthesized to show a bent and flexible backbone. Reactions of papoa with ZnX2 (X=Cl, Br, and I) gave the dinuclear macrocycles ([ZnX2(papoa)]2; X=Cl ( 1 a ), Br ( 2 a ), I ( 3 )), the structure of which was determined by X‐ray diffraction. Notably, the less bulky Cl and Br compounds afforded the coordinated imine in acetone (i.e., [ZnX2(papoi)]2, papoi=N‐(4‐(4‐(propan‐2‐ylideneamino)phenoxy)phenyl)isonicotinamide; X=Cl ( 1 b ), Br ( 2 b )), whereas the iodine one only gave the coordinated amine compound 3 under the same reaction condition. In fact, the coordinated imine can return to the amine analogue upon exposure to air or in DMSO, which has been monitored by 1H NMR spectroscopy and powder X‐ray diffraction. Both the dinuclear [Zn(papoa)(NO3)2]2 ( 4 a ) and the 1D [Zn(papoa)2(NO3)2]n ( 4 b ) were formed from the reaction of Zn(NO3)2 and papoa in mixed solvents with acetone and acetonitrile, respectively. In addition, Cd(ClO4)2 can react with papoa to give the 1D framework {[Cd(papoa)2(CH3CN)2](ClO4)2}n ( 5 a ) and the 2D framework [Cd(papoa)2(ClO4)2]n ( 5 b ), depending on the solvent used, that is, MeOH and CH3CN, respectively. Importantly, the 1D framework with axially coordinated CH3CN molecules and the 2D framework with axially coordinated ClO4? ions can be interconverted by heating and grinding in the presence of CH3CN, respectively. Such a reversible structural transformation process was proven by PXRD studies. 相似文献
9.
Supramolecular inclusion complexes (ICs) involving polyhedral oligomeric silsesquioxane (POSS) capped poly(?‐caprolactone) (PCL) and α‐cyclodextrin (α‐CD) were investigated. POSS‐terminated PCLs with various molecular weights were prepared via the ring‐opening polymerization of ?‐caprolactone (CL) with 3‐hydroxypropylheptaphenyl POSS as an initiator. Because of the presence of the bulky silsesquioxane terminal group, the inclusion complexation between α‐CD and the POSS‐capped PCL was carried out only with a single end of a PCL chain threading inside the cavity of α‐CD, which allowed the evaluation of the effect of the POSS terminal groups on the efficiency of the inclusion complexation. The X‐ray diffraction results indicated that the organic–inorganic ICs had a channel‐type crystalline structure. The stoichiometry of the organic–inorganic ICs was quite dependent on the molecular weights of the POSS‐capped PCLs. With moderate molecular weights of the POSS‐capped PCLs (e.g., Mn =3860 or 9880), the stoichiometry was 1:1 mol/mol (CL unit/α‐CD), which was close to the literature value based on the inclusion complexation of α‐CD with normal linear PCL chains with comparable molecular weights. When the PCL chains were shorter (e.g., for the POSS‐capped PCL of Mn = 1720 or 2490), the efficiency of the inclusion complexation decreased. The decreased efficiency of the inclusion complexation could be attributed to the lower mobility of the bulky POSS group, which restricted the motion of the PCL chain attached to the silsesquioxane cage. This effect was pronounced with the decreasing length of the PCL chains. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1247–1259, 2007 相似文献
10.
Synthesis of hyperbranched polyacetals via an + b2‐type polyaddition (n = 3, 8, 18, and 21): Candidate resists for extreme ultraviolet lithography 下载免费PDF全文
Hiroto Kudo Shuhei Matsubara Hiroki Yamamoto Takahiro Kozawa 《Journal of polymer science. Part A, Polymer chemistry》2015,53(20):2343-2350
Polyaddition (An + B2) reactions of 1,1,1‐tris(4‐hydoxyphenyl) ethane (THPE; A3‐type monomer), calix[4]resorcinarene (CRA[4]; A8‐type monomer), α‐cyclodextrin (α‐CD; A18‐type monomer), and β‐cyclodextrin (β‐CD; A21‐type monomer) with 1,4‐bis(4‐vinyloxy)cyclohexane (BVOC; B2‐type monomer) afforded corresponding soluble hyperbranched polyacetals. The physical properties, including solubility, thermal stability, and film‐forming ability, the ultraviolet‐induced degradation reactivity, and the solubility‐switch in an extreme ultraviolet (EUV) exposure tool indicated that poly(THPE‐co‐BVOC) and poly(CRA[4]‐co‐BVOC) are candidate next‐generation photo‐resists. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2343–2350 相似文献
11.
《无机化学与普通化学杂志》2018,644(3):142-148
Three diacylthioureas 1,4‐C6H4[C(O)NHC(S)NHAr]2 (Ar = 2,6‐iPr2C6H3) ( L1 , 1 ), 1,3‐C6H4[C(O)NHC(S)NHAr]2 ( L2 , 2 ), and 1,3‐C6H4[C(O)NHC(S)NHAr′]2 (Ar′ = 2,6‐Me2C6H3) ( L3 , 3 ) were synthesized and characterized. The CuI complexes from the reactions of bipodal ligands Ln with CuX (X = Cl, Br, I) were structurally investigated by single‐crystal X‐ray diffraction methods. Treatment of L1 with CuX gave the metallamacrocyclic complexes ( L1 CuX)2 [X = Cl ( 4 ), Br ( 5 ), I ( 6 )] with the ligand to metal in a ratio of 2:2, where both sulfur and halide anions function as terminal substituents. In contrast, when L2 or L3 was reacted with CuBr, the two Ln ligands coordinate to four copper atoms each in a bridging and terminal fashion to yield [ Ln (CuBr)2]2 [n = 2 ( 7 ), 3 ( 8 )]. The obtained S4Cu4Br4 core contains all four bromide anions in bridging positions. The reaction of L3 with CuX (X = Cl, I) gave the 3:3 trinuclear complexes ( L3 CuX)3 [X = Cl ( 9 ) I ( 10 )], interconnected by halide bridges. The obtained diacylthioureas ( 1 – 3 ) and their CuI complexes ( 4 – 10 ) were also characterized by elemental analysis, FT‐IR, 1H and 13C NMR spectroscopy. 相似文献
12.
《Magnetic resonance in chemistry : MRC》2002,40(3):182-186
15N NMR data of a series of 3‐alkyl[aryl] substituted 5‐trichloromethyl‐1,2‐dimethyl‐1H‐pyrazolium chlorides (where the 3‐substituents are H, Me, Et, n‐Pr, n‐Bu, n‐Pe, n‐Hex, (CH2)5CO2Et, CH2Br, Ph and 4‐Br‐C6H4), are reported. The 15N substituent chemical shifts (SCS) parameters are determined and these data are compared with the 13C SCS values and data obtained by MO calculations. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
13.
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
14.
Synthesis of a Structure‐Definite α‐Cyclodextrin‐Based Macromolecular [3]Rotaxane Using a Size‐Complementary Method 下载免费PDF全文
Dr. Yosuke Akae Dr. Hiromitsu Sogawa Prof. Toshikazu Takata 《Angewandte Chemie (International ed. in English)》2018,57(36):11742-11746
The challenging synthesis of an α‐cyclodextrin (CD)‐based macromolecular rotaxane with definite structure was fulfilled using a size‐complementary method. A new peracetylated (PAc) α‐CD‐based size‐complementary [3]rotaxane was prepared and its thermal dissociation kinetics studied. The de‐slippage mechanism was found to be different from that of the native α‐CD‐based system. PAcα‐CD‐based size‐complementary [3]rotaxanes were employed as initiators for a ring‐opening polymerization of ?‐caprolactone to obtain the macromolecular [3]rotaxanes. Detailed investigation of component dissociation showed the highly movable character of the wheel on the polymer main chain. A general method for controlling the movement of wheels in rotaxane frameworks, even in polymer systems, was established. This will enable the development of new supramolecular architectures and molecular machines. 相似文献
15.
Jrmy Scelle Hugo Vervoitte Laurent Bouteiller Lise-Marie Chamoreau Matthieu Sollogoub Guillaume Vives Bernold Hasenknopf 《Chemical science》2022,13(8):2218
The encapsulation of guests in a confined space enables unusual conformations and reactivities. In particular, the compression of akyl chains has been obtained by self-assembled molecular capsules but such an effect has not been reported in solution for pseudorotaxane architectures. By exploiting the tendency of cyclodextrin (CD) to form head to head [3]pseudorotaxanes and the hydrogen bonding abilities of phosphate groups, we have studied the effect of the CD dimer cavity on the conformation of threaded α,ω-alkyl-diphosphate axles. The formation of [2]pseudorotaxanes and [3]pseudorotaxanes was investigated by a combination of NMR, ITC and X-ray diffraction techniques. In the solid state, the [3]pseudorotaxane with a C8 axle presents a fully extended conformation with both terminal phosphate groups interacting with hydroxyl groups of the primary rim of CDs. Such hydrogen bonding interactions are also present with the C9 and C10 axles resulting in a compression of the alkyl chain with gauche conformations in the solid state. NMR studies have shown that this effect is maintained in solution resulting in a size-dependent progressive compression of the alkyl chain by the CD [3]pseudorotaxane architecture for C9, C10 and C11 axles.Alkyl chain compression of alkanediphosphate guests was achieved by head-to-head cyclodextrin [3]pseudorotaxanes in a mechanostereoselective self-assembly process. 相似文献
16.
Kyung‐Moo Shin Tungalag Dong Yong He Yoshio Inoue 《Journal of Polymer Science.Polymer Physics》2005,43(12):1433-1440
The effect of molecular weight of poly(ε‐caprolactone) (PCL) on the formation and stability of inclusion complexes (ICs) between α‐cyclodextrin (α‐CD) and PCL was investigated by FTIR, WAXD, and DSC measurements. ICs between α‐CD and PCLs with a wide range of number‐average molecular weight, Mn = 1.21 × 104 – 1.79 × 105, were prepared by mixing the aqueous solution of CD and acetone solution of PCL followed by stirring at 60 °C for 1h and at the room temperature for 1 day. FTIR, WAXD, and DSC measurement showed the PCL chains were included into the α‐CD cavity, and the crystallization of PCL was suppressed in the α‐CD cavity. Stoichiometry and yield of each IC varied with the molecular weight of guest PCL, and the effect of IC formation on the crystallization behaviour of guest polymer decreased with the increase of molecular weight of guest polymer. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1433–1440, 2005 相似文献
17.
Organometallic Compounds of Copper. XVIII. On the Reaction of the Alkyne Copper(I) Complexes [CuX(S‐Alkyne)] (X = Cl, Br, I; S‐Alkyne = 3,3,6,6‐Tetramethyl‐1‐thiacyclohept‐4‐yne) with the Phosphanes PMe3 and Ph2PCH2CH2PPh2 (dppe) The alkyne copper(I) halide complexes [CuX(S‐Alkyne)]n ( 2 ) ( 2 a : X = Cl, 2 b : X = Br, 2 c : X = I; S‐Alkyne = 3,3,6,6‐tetramethyl‐1‐thiacyclohept‐4‐yne; n = 2, ∞) add the phosphanes PMe3 and Ph2PCH2CH2PPh2 (dppe) to form the mono‐ and dinuclear copper compounds [(S‐Alkyne)CuX(PMe3)] ( 6 ) ( 6 a : X = Cl, 6 b : X = Br) and [(S‐Alkyne)CuX(μ‐dppe)CuX(S‐Alkyne)] ( 7 a : X = Cl, 7 b : X = Br, 7 c : X = I), respectively. By‐product in the reaction of 2 a with dppe is the tetranuclear complex [(S‐Alkyne)Cu(μ‐X)2Cu(μ‐dppe)2Cu(μ‐X)2Cu(S‐Alkyne)] ( 8 ). In case of the compounds 7 prolonged reaction times yield the alkyne‐free dinuclear copper complexes [Cu2X2(dppe)3] ( 9 ) ( 9 a : X = Cl, 9 b : X = Br, 9 c : X = I)). X‐ray diffraction studies were carried out with the new compounds 6 a , 6 b , 7 b , 8 , and 9 c . 相似文献
18.
Laijin Tian Hongjun Yang Xiaoliang Zheng Zhonghai Ni Dongmei Yan Linglan Tu Jianzhuang Jiang 《应用有机金属化学》2009,23(1):24-31
Four new diorganotin(IV) complexes of N‐(5‐halosalicylidene)tryptophane, R2Sn[5‐X‐2‐OC6H3CH?NCH(CH2Ind)COO] [Ind = 3‐indolyl; R, X = Et, Cl ( 1 ); Et, Br( 2 ); n‐Bu, Cl ( 3 ); n‐Bu, Br ( 4 )], were synthesized and characterized by elemental analysis, IR and NMR (1H, 13C and 119Sn) spectra. The crystal structures of complexes 1 – 3 were determined by X‐ray single crystal diffraction and showed that the tin atoms are in a distorted trigonal bipyramidal geometry and form five‐ and six‐membered chelate rings with the tridentate ligand. Intermolecular weak interactions in 1–3 link molecules, respectively, into a two‐dimensional array, a one‐dimensional infinite chain and a one‐dimensional double‐chain supramolecular structure. Bioassay results of the compounds indicated that the dibutyltin complexes 3 and 4 have potent in vitro cytotoxic activity against two human tumor cell lines, CoLo205 and Bcap37, while the diethyltin complexes 1 and 2 display weak cytotoxic activity. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
19.
α‐Imidazolformylarylhydrazine 2 and α‐[1,2,4]triazolformylarylhydrazine 3 have been synthesized through the nucleophilic substitution reaction of 1 with imidazole and 1,2,4‐triazole, respectively. 2,2′‐Diaryl‐2H,2′H‐[4,4′]bi[[1,2,4]‐triazolyl]‐3,3′‐dione 4 was obtained from the cycloaddition of α‐chloroformylarylhydrazine hydrochloride 1 with 1,2,4‐triazole at 60 °C and in absence of n‐Bu3N. The inducing factor for cycloaddition of 1 with 1,2,4‐triazole was ascertained as hydrogen ion by the formation of 4 from the reaction of 3 with hydrochloric acid. 4 was also acquired from the reaction of 3 with 1 and this could confirm the reaction route for cycloaddition of 1 with 1,2,4‐triazole. Some acylation reagents were applied to induce the cyclization reaction of 2 and 3.1 possessing chloroformyl group could induce the cyclization of 2 to give 2‐aryl‐4‐(2‐aryl‐4‐vinyl‐semicarbazide‐4‐yl)‐2,4‐dihydro‐[1,2,4]‐triazol‐3‐one 6. 7 was obtained from the cyclization of 2 induced by some acyl chlorides. Acetic acid anhydride like acetyl chloride also could react with 2 to produce 7D . 5‐Substituted‐3‐aryl‐3H‐[1,3,4]oxadiazol‐2‐one 8 was produced from the cyclization reaction of 3 induced by some acyl chlorides or acetic acid anhydride. The 1,2,4‐triazole group of 3 played a role as a leaving group in the course of cyclization reaction. This was confirmed by the same product 8 which was acquired from the reaction of 1 , possessing a better leaving group: Cl, with some acyl chlorides or acetic acid anhydride. 相似文献
20.
Bin Wang Dr. Hua‐Ji Liu Xiao‐Bin Fu Prof. Dr. Yefeng Yao Prof. Dr. Yu Chen 《化学:亚洲杂志》2015,10(8):1690-1697
Hyperbranched polyethylenimine terminated with isobutyramide groups (HPEI‐IBAm), 4‐(phenylazo)benzoic acid (PABA), and α‐cyclodextrin (α‐CD) were assembled together at pH≈7 to form the three‐component supramolecular complexes that were verified by 1H and 2D ROESY 1H NMR spectroscopy. UV/Vis spectrometric titration experiments showed that the content of α‐CD in the three‐component complexes was less than the feed amount and it was difficult for all the PABA units in the complexes to further form complexes with α‐CD. The obtained three‐component supramolecular complexes exhibited thermoresponsive properties in water. Increasing the α‐CD concentration led to a sharp increase in the cloud point temperature (Tcp) at the beginning, but after the [α‐CD]/[PABA] ratio was in the region of 1.3–1.6, the Tcp increased gradually When the concentration of α‐CD was low, a higher concentration of PABA led to a lower Tcp, however, the opposite was observed when the concentration of α‐CD was high. For the three‐component complex, increasing the α‐CD concentration at pH≈7 or at pH≈9 led to different Tcp temperatures. In the low α‐CD concentration range, adjusting the pH from ≈7–≈9 resulted in an increase in the Tcp, similar but not so pronounced as that of the two‐component system of HPEI‐IBAm/[PABA]. When the concentration of α‐CD was high, adjusting the pH from ≈7–≈9 decreased the Tcp; this observation is different to that of the two‐component system of HPEI‐IBAm/[PABA]. Reversible trans‐to‐cis photoisomerization of azobenzene units in the complexes occurred, following irradiation with UV or visible light. Trans‐to‐cis isomerization of azobenzene units decreased the Tcp. However, this result differed to that of the two‐component system of HPEI‐IBAm/PABA. 相似文献