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1.
用~1HNMR方法研究了溶液中大环化合物1,12-二氮杂-3,4:9,10-二本并-5,8-二氧杂环十五烷-N,N’-二乙酸盐的构象.NMR变温实验表明,在溶液中大环与Zn(Ⅱ)、Ni(Ⅱ)、Co(Ⅱ)的配合物环上醚氧不参与配位,其中Ni(Ⅱ)配合物为低自旋反磁性的平面四方形配位.  相似文献   

2.
1 INTRODUCTIONThe coordination chemistry of macrocyclic compounds has received considerable attention for several decades, primarily due to its importance in biological processes[1]. A variety of 12 ~ 15 membered polyamine and polyoxotetraaza macrocycles have been found to be especially effective in stabilizing oxidation states of the complexed metal ion that are inaccessible for complexes with noncyclic ligands[2~5]. Very recently, we demonstrated that a series of macrocyclic oxamido Sch…  相似文献   

3.
Reduction of 2,3:9,10-dibenzo-5,12-diaza-1,8-dioxacylotetradecane-5,11-diene( 1 ) with sodium borohydride in ethanol generates 2,3:9,10-dibenzo-5,12-diaza-1,8-dioxacyclotetradecane( 2 ) in high yield. The macrocyclic ligand 2,3:9,10-dibenzo-5,12-diaza-1,8-dioxacyclotetradecane-N,N′-diacetic acid ( 3 ) has been synthesized and characterized. In addition, reaction of ( 2 ) with an excess of acrylonitrile gives 2,3:9,10-dibenzo-5,12-diaza-1,8-dioxacyclotetradecane-N,N′-di(2-cyanoethyl) ( 4 ). Several new complexes of these ligands with nickel(II), copper(II) and cobalt(II) have been prepared and identified. The structures of these complexes are proposed on the basis of elemental analysis, 1H, 13C-NMR, IR, UV-VIS spectra, magnetic susceptibility and conductivity data.  相似文献   

4.
近年来,带电离官能团取代的大环成为大环化学研究的热点之一 [1~ 3]。这类大环除了环的腔径及环上配位原子种类对不同离子具有配位选择性外,其电离官能团的酸碱效应,也产生对 pH敏感的配位选择性。另外,由于大环骨架的相对刚性,刚柔相济的作用还起到提高配位能力,改进选择性的效果。迄今为止,人们对全氮取代的氮杂大环及其配合物作了相当深入的研究 [4~ 6],部分氮取代的氮氧杂大环及其配合物的研究还很少 [7,8]。从研究配体配位性能的观点来看,改变大环上氮取代的电离官能团数目可以进一步开发出具有良好选择性的配体。本文报道…  相似文献   

5.
Reaction of trans-[Ru(VI)(L)(O)(2)](2+) (1, L = 1,12-dimethyl-3,4:9,10-dibenzo-1,12-diaza-5,8-dioxacyclopentadecane, a tetradentate macrocyclic ligand with N(2)O(2) donor atoms) with nitrite in aqueous solution or in H(2)O/CH(3)CN produces the corresponding (nitrato)oxoruthenium(IV) species, trans-[Ru(IV)(L)(O)(ONO(2))](+) (2), which then undergoes relatively slow aquation to give trans-[Ru(IV)(L)(O)(OH(2))](2+). These processes have been monitored by both ESI/MS and UV/vis spectrophotometry. The structure of trans-[Ru(IV)(L)(O)(ONO(2))](+) (2) has been determined by X-ray crystallography. The ruthenium center adopts a distorted octahedral geometry with the oxo and the nitrato ligands trans to each other. The Ru=O distance is 1.735(3) A, the Ru-ONO(2) distance is 2.163(4) A, and the Ru-O-NO(2) angle is 138.46(35) degrees . Reaction of trans-[Ru(VI)(L)((18)O)(2)](2+) (1-(18)O(2)) with N(16)O(2)(-) in H(2)O/CH(3)CN produces the (18)O-enriched (nitrato)oxoruthenium(IV) species 2-(18)O(2). Analysis of the ESI/MS spectrum of 2-(18)O(2) suggests that scrambling of the (18)O atoms has occurred. A mechanism that involves linkage isomerization of the nitrato ligand and reversible oxygen atom transfer is proposed.  相似文献   

6.
CrystalStructureof[Cu(C_(21)H_(25)N_2O_4)(H_2O)_2]·NO_3·2H_2OWuJie-Ying;XieFu-Xin;TianYu-Peng;ChenYao;NiShi-Sheng;DuShao-Wu;WuXin...  相似文献   

7.
1 INTRODUCTION The knowledge of all non-covalent interactions, such as strong and weak hydrogen bonds and p…p interactions, is important to the supramolecular chemistry, biochemistry, crystal engineering and material science[1~7]. Several mononuclear complexes of macrocyclic oxamido Schiff base ligands with phenyls have been used as 揷omplex ligands?to design polynuclear complexes[8~11]. Herein we report the molecular and crystal structures, CH贩稯 hy- drogen bonding and p…p stacki…  相似文献   

8.
卜显和  曹希伟 《结构化学》1996,15(6):499-502
1,4,7,10-四氮杂环十二烷(cyclen)与2-氯甲基吡啶反应获得新型八齿配体1,4,7,10-四(2-甲基吡啶基)-1,4,7,10-四氮杂环十二烷(L)。该配体与Zn(ClO_4)_2在水溶液中反应生成无色晶体ZnL(ClO_4)_2(1)。晶体结构测定表明:化合物1,C_32H_40-Cl_2N_8O_8Zn,属单斜晶系,空间群P2_1/c,α=9.822(5),b=10.721(3),c=33.900(2)A,β=90.54(4)°,V=3570(4)A3,D_c=1.49g/cm ̄3,Z=4,F(000)=1664,Mr=801.0。1888个可观测衍射点参与修正,R=0.069,Rw=0.072。在化合物1中,Zn原子采取六配位的变形八面体构型,在4个吡啶侧臂之中,只有相对的两个参与配位,而另外的两个有一个远离配位中心,另一个吡啶上的氮原子与锌原子之间存在因二级化学键而引起的弱相互作用。  相似文献   

9.
CrystalStructureofCopper(Ⅱ)Complexwith3-Hydroxyl-1,5-diazacyclooctaneLiuSheng-Hua;XueGuo-Ping;FuEn-Qin;WuChengTai(Departmento...  相似文献   

10.
CrystalStructureof[Ru(taab)(DMF)_2]·[(CIO_4)_2]¥DuanChun-Ying;LuZhong-Lin;TianYu-Peng;YouXiao-Zeng;ChenYao(CoordinationChemist?..  相似文献   

11.
A facile route is described for the synthesis of a series of macrocyclic tetraamides 1, 4, 9, 12 - tetraazacyclo - 2, 3, 6, 7, 10, 11, 14, 15-tetrabenzo-cetanan - 5, 8, 13, 16 - tetraone (TCTCT), 1, 4, 10, 13 - tetraazacyclo -2, 3, 6, 8, 11, 12, 15, 17-tetrabenzo-octadecan-5, 9, 14, 18-tetraone(TCTOT) and 1, 4, 10, 13-tetraaza-cyclo-2, 3, 11, 12-dibenzo-6, 8, 15, 17-dipyrdyl-octadecan-5, 9, 14, 18-tetraone (TCPOT) derived from 1, 2-diaminobenzene based on a stepwise approach using diacid dichloride (1, 2-diacid dichloride benzene, 1, 3- diacid dichloride benzene, 2, 6 - diacid dichloride pyridine) or mix dianhydrides for ring closure. This method is applicable for the preparation of a variety of receptors of various ring size, heteroatom substitution and pendant chains.  相似文献   

12.
《Analytical letters》2012,45(11):2201-2215
ABSTRACT

DP+ ion-selective PVC membrane electrode based on 2,3,11,12-dibenzo-5,9-diaza-4,9(10)-cis-diimino-1,13-dioxacyclopentadecane as a novel macrocyclic diimine crown ether is proposed. o-Nitrophenyl octyl ether as plasticizer and potassium tetrakis(4-chlorophenyl)borate as lipophilic salt were used. The electrode exhibits a Nernstian response for 1.0 x 10?2-1.0 x 10?6 mol 1?1 DPCl with a slope of 58 mVdecade?1. The detection limit is 2.5 x 10?7 mol 1?1. The electrode response was stable over a wide pH range (3-11). The lifetime of the electrode was about 2 months. The electrode shows a high selectivity towards inorganic cations. Among the organic cations tested, only hexadecyltrimethylammonium ion interferes. The electrode was suitable for determining the critical micelle concentration and as an end-point detector in the potentiometric titration of the cationic surfactants.  相似文献   

13.
<正> C11H12N2MoO5, Mr = 348.17, orthorhombic, space group p212121,a= 7.048(1), b = 11.060(4), c = 18.039(7) A, V = 1406.2(8) A3, Z = 4, D x=1.645, Dm = 1.61 (flotation in aqueous KI) g cm-3 , graphite-monochromatizedMo-Kα,λ = 0.71069 A, μ = 9.25 cm-1, F(OOO) = 695.73, T = 295°K, final RF =0.035 and RwF2 = 0.051 for 1335 observed reflections with |F0| > 3σ(|F0|). The measured molecular dimensions.reflect the trans influence and steric bulk of the organic cage ligand.  相似文献   

14.
Convenient syntheses of the tetramines 2, 3:10, 11-dibenzo-1, 5, 8, 12-tetraazadodecane, (L1, and 3, 4:9, 10-dibenzo-1, 5, 8, 12-tetraazadodecane (L2), are described. Both ligands form complexes with Ni(II), Zn(II) and Cd(II). The X-ray structure of [Cd(L1)I2), confirms a five coordinate geometry for the Cd atom, where the two iodines are bonded to the metal and (L1) acts as a tridentate ligand. The complex crystallises in the monoclinic space group P21/c with a = 19.741(4) Å, b = 8.726(3) Å, c = 12.221(4) Å, and β = 104.55(3)°. The structure was refined to R = 0.062 for 1051 reflections.  相似文献   

15.
Two new monoprotonated products of macrocyclic polyamine 1,4,7-trimethyl- 1,4,7-triazacyclononane (Me3 [9]aneN3), (Me3 [9]aneN3H) (SO3CF3) 1 (C10H22N3O3SF3, Mr=321.36) and (Me3[9]aneN3H)I 2 (C9H22N3I, Mr=299.20) were obtained by the reactions of Me3[9]aneN3 and yttrium triflate or ytterbium diiodide as the unexpected products. The crystal structures of compounds 1 and 2 have been determined. Crystal 1is orthorhombic, space group P212121(#19), a =12. 609(3), b=13. 531(1), c=9.225(3) A, V=1573.9(7) A3, Z=4, Dc=1. 356g/cm3, μ=2.47cm- 1, F (000) = 680 and R= 0. 052, Rw= 0. 052 for 807 unique reflections with I> 2σ(I). Crystal 2 belongs to the orthorhombic system with space group P212121 (# 19), a=11.417(2), b=13.099(3), c=8.762(2) A, V=1310.5(4) A3, Z=4, Dc=1. 516 g/cm3, μ= 24.14 cm-1, F(000)=600 and R=0. 035, Rw=0. 042 for 1427 u-nique reflections with I>3σ(I). The two structures contain the same cyclic framework in which the acid proton is bonded to an amine nitrogen. This proton exhibits strong intramolecular hydrogen bonds with the other two nitrogen atoms. The methyl groups are directed away from the ring cavity. The bond distance between acid proton and an amine nitrogen in compound 2 is extremely short. The bond angles for 1 and 2 also exhibit obvous diversity inside of triazacyclononae.  相似文献   

16.
<正> [(C6H5)4P]Cu(S2C6H4)2(Ⅰ),Mr = 683. 39,monoclinic,space group C2/c,a=16. 099 (4),b= 11. 913(3) ,c = 16: 715(9) A ,β=97. 13(4)°, v = 3180. 7 A3,z=4.MoKa radiation,λ= 0. 71069A ,Dc= 1. 427g/cm3,μ= 10. 1cm-1,F(000) = 1400,R=0. 061 and Rw = 0. 068 for 2189 reflections with Ⅰ>3σ(Ⅰ). [(C6H5)4P]Cu (S2C7H6)2(Ⅰ),Mr = 711. 45,monoclinic,space group C2/c,a=16. 501(6),b = 37. 461 (15),c=16. 684(4)A,β=96. 70(4)°, v= 10248. 8(46) A3,z= 12. MoKa radiation, λ= 0. 71069A,Dc=1.383g/cm3,μ=9. 45cm-1,F(000).= 4416,R= 0. 074 and Rw= 0. 078 for 2085 reflections with I>2σ(I)(1). The copper atom in the complexes is surrounded by four sulfur atoms from two dithiolato ligands in an approximate, square-plane. The average Cu-S distances of the copmplexes(Ⅰ) and (Ⅱ) are 2. 179 and 2. 178 A, respectively.  相似文献   

17.
1 INTRODUCTIONOneofourcurrentinterestsfocusesonthedesignandsynthesesofpolyazamacrocyclicligands,andthestabilitiesofcorrespondingmetalcomplexes.Twopolyazadiphenolmacrocycles,R(babp) 2 (dfc) 2 andR (bac) 2 (dfp) 2 ;[1 ]oneoctaaza macrocycle,BPBD ;[2 ,3]andseveralhexaazama…  相似文献   

18.
Aguilar JC  Miguel ER  Gyves J  Bartsch RA  Kim M 《Talanta》2001,54(6):1195-1204
The ligands 4,7-diaza-2,3,8,9-dibenzo-15-crown-5 (L1), 4,10-diaza-2,3,11,12-dibenzo-18-crown-6 (L2), 4,10-diaza-2,3,11,12-di(4′-tert-butylbenzo)-18-crown-6 (L3) and N,N-di(methylenecarboxyethoxy) 4,10-diaza-2,3,11,12-dibenzo-18-crown-6 (L4) have been prepared. Partition coefficients and acid dissociation constants for these four diazadibenzocrown ether compounds were determined in water-chloroform. Their effectiveness was assessed in solvent extraction of Pb2+ from aqueous solutions into toluene. Ligands L3 and L4 provide high selectivity for Pb2+ over Cd2+ and Zn2+ in transport across plasticized cellulose triacetate membranes.  相似文献   

19.
1 INTRODUCTIONThemaintargetinmacrocyclicdesignistosynthesizemacrocycleswhichareabletodiscriminateamongthedifferentmetalcations.Manyfactorsinfluencingtheselectivitiesofmacrocyclesforcationshavebeendeterminedsuchassubstituenteffect,donoratomictypesand…  相似文献   

20.
Lam WW  Yiu SM  Yiu DT  Lau TC  Yip WP  Che CM 《Inorganic chemistry》2003,42(24):8011-8018
The oxidations of a series of 21 alkylaromatic compounds by trans-[Ru(VI)(L)(O)(2)](2+) (L = 1,12-dimethyl-3,4:9,10-dibenzo-1,12-diaza-5,8-dioxacyclopentadecane) have been studied in CH(3)CN. Toluene is oxidized to benzaldehyde and a small amount of benzyl alcohol. 9,10-Dihydroanthracene is oxidized to anthracene and anthraquinone. Other substrates give oxygenated products. The kinetics of the reactions were monitored by UV-vis spectrophotometry, and the rate law is: -d[Ru(VI)]/dt = k(2)[Ru(VI)][ArCH(3)]. The kinetic isotope effects for the oxidation of toluene/d(8)-toluene and fluorene/d(10)-fluorene are 15 and 10.5, respectively. A plot of Delta H(++) versus Delta S(++) is linear, suggesting a common mechanism for all the substrates. In the oxidation of para-substituted toluenes, a linear correlation between log k(2) and sigma(0) values is observed, consistent with a benzyl radical intermediate. A linear correlation between Delta G(++) and Delta H(0) (the difference between the strength of the bond being broken and that being formed in a H-atom transfer step) is also found, which strongly supports a hydrogen atom transfer mechanism for the oxidation of these substrates by trans-[Ru(VI)(L)(O)(2)](2+). The slope of (0.61 +/- 0.06) is in reasonable agreement with the theoretical slope of 0.5 predicted by Marcus theory.  相似文献   

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