基于[(Tp)Fe(CN)3]-氰基桥联双核配合物的合成、结构和磁性研究

采用[TpFe^Ⅲ(CN)₃]^-作为构筑基块，合成并表征了一个氰基桥联双核配合物[(Tp)Fe^Ⅲ(CN)₃Cu^Ⅱ(bpy)₂]ClO₄·CH₃OH (1)。对化合物1进行了晶体结构分析，其晶胞参数为a=0.904 26(5) nm，b=1.352 56(7) nm，c=1.556 02(8) nm，α=106.08(1)°，β=95.79(1)°，γ=91.01(1)°，P1空间群。在这个化合物中，[TpFe^Ⅲ(CN)₃]通过其中1个氰基与[Cu(bpy)₂]²⁺桥联，而另外2个氰基未参与配位。磁性研究表明，在化合物1中，Cu(Ⅱ)与Fe(Ⅲ)离子之间表现为铁磁相互作用。用哈密顿函数H=-2JS_FeS_Cu对其χ_MT-T曲线进行了拟合，得到1的朗德因子g=2.34和交换常数J=5.52 cm^-1。     

氰根桥联三核异金属配合物的合成、晶体结构及磁性研究

采用[(Tp)Fe(CN)₃]-(Tp=hydrotris(pyrazolyl)borate)与Mn(Ac)₂·4H₂O反应，合成了氰根桥联的异金属三核配合物[Mn(phen)₂][(Tp)Fe(CN)₃]₂·5H₂O (1)(phen=1，10-phenanthroline)，并对其结构和磁性进行了研究。晶体结构分析结果表明该化合物晶体属于三斜晶系，P1空间群。在该配合物中，Mn(Ⅱ)与2个phen分子及2个[(Tp)Fe(CN)₃]^-配位，形成一种弯曲的三核结构。磁性测量结果表明，Mn(Ⅱ)和Fe(Ⅲ)之间通过氰根桥联产生弱的反铁磁相互作用。     

氰根桥连的FeⅢMnⅡ链中磁性作用的调控

基于三氰构筑单元合成了两个氰基桥联的Fe^ⅢMn^Ⅱ一维链, {[Fe(Tp)(CN)₃]₂[Mn(bib)]}·CH₃OH·2H₂O (1)和{[Fe(pzTp)(CN)₃]₂[Mn(bib)]}·3H₂O (2)。1和2中的双之字链通过刚性的双齿配体固定排列方式并连接成二维结构, 链内Fe^Ⅲ和Mn^Ⅱ之间的磁相互作用可以通过改变链中配体的位阻调控。     

基于双齿咪唑席夫碱配体的两个手性自旋转换铁(Ⅱ)配合物

以含有苯环和咪唑环的手性双齿席夫碱为配体, 合成了2个纯手性单核自旋转换铁(Ⅱ)配合物fac-Δ-[Fe(S-L₁)₃][ClO₄]₂ (1), mer-Λ-[Fe(R-L₂)₃][ClO₄]₂·Et₂O (2)(L₁=1-对氯苯基-N-(1-正丙烯基-1H-咪唑-2-亚甲基)乙胺;L₂=1-苯基-N-(1-异丙烯基-1H-咪唑-2-亚甲基)乙胺)。利用X-射线单晶衍射、元素分析(EA)、红外光谱(IR)、核磁共振氢谱(¹H NMR)、紫外光谱(UV)、圆二光谱(CD)等手段对配合物结构进行了表征。X-射线单晶衍射表明在配合物1和2中, 铁(Ⅱ)金属中心与3个不对称双齿手性席夫碱配体中的6个氮原子配位形成八面体配位环境。配合物1中每个结构基元中包含1个[Fe(L_n)₃]²⁺阳离子和2个高氯酸根阴离子。而配合物2中每个结构基元中包含2个[Fe(L_n)₃]²⁺阳离子、4个高氯酸根阴离子和1个乙醚分子。由于铁(Ⅱ)中心周围手性配体的螺旋协调配位使[Fe(L_n)₃]²⁺形成单一构型。Fe(Ⅱ)-N键长表明配合物1中的铁(Ⅱ)在低自旋状态, 而配合物2中的铁(Ⅱ)在高自旋状态。在[Fe(L_n)₃]²⁺中, 相邻配体中的苯环和咪唑环形成分子内π-π相互作用。配合物1和2通过分子间C-H…π和C-Cl…π相互作用形成超分子结构。CD光谱证实配合物1和2在溶液中的光学活性。磁性测试表明配合物1和2分别在372 K和146 K发生自旋转换。由于配合物1和2具有不同的堆积方式和分子间相互作用, 导致1和2表现出不同的自旋转换温度。     

基于双齿咪唑席夫碱配体的两个手性自旋转换铁(Ⅱ)配合物

以含有苯环和咪唑环的手性双齿席夫碱为配体, 合成了2个纯手性单核自旋转换铁(Ⅱ)配合物fac-Δ -[Fe(S-L₁)₃][ClO₄]₂ (1), mer-Λ -[Fe(R-L₂)₃][ClO₄]2· Et₂O (2)(L₁=1-对氯苯基-N-(1-正丙烯基-¹H-咪唑-2-亚甲基)乙胺; L₂=1-苯基-N-(1-异丙烯基-1H-咪唑-2-亚甲基)乙胺)。利用X-射线单晶衍射、元素分析(EA)、红外光谱(IR)、核磁共振氢谱(¹H NMR)、紫外光谱(UV)、圆二光谱(CD)等手段对配合物结构进行了表征。X-射线单晶衍射表明在配合物1和2中, 铁(Ⅱ)金属中心与3个不对称双齿手性席夫碱配体中的6个氮原子配位形成八面体配位环境。配合物1中每个结构基元中包含1个[Fe(L_n)₃]²⁺阳离子和2个高氯酸根阴离子。而配合物2中每个结构基元中包含2个[Fe(L_n)₃]²⁺阳离子、4个高氯酸根阴离子和1个乙醚分子。由于铁(Ⅱ)中心周围手性配体的螺旋协调配位使[Fe(L_n)₃]²⁺形成单一构型。Fe(Ⅱ)-N键长表明配合物1中的铁(Ⅱ)在低自旋状态, 而配合物2中的铁(Ⅱ)在高自旋状态。在[Fe(L_n)₃]²⁺中, 相邻配体中的苯环和咪唑环形成分子内π-π相互作用。配合物1和2通过分子间C-H…π和C-Cl…π相互作用形成超分子结构。CD光谱证实配合物1和2在溶液中的光学活性。磁性测试表明配合物1和2分别在372 K和146 K发生自旋转换。由于配合物1和2具有不同的堆积方式和分子间相互作用, 导致1和2表现出不同的自旋转换温度。     

含大环[Ni([15]aneN5]2+氰基桥联四核簇合物的合成、结构和磁性质

用1,4,7,10,13-五氮十五烷(cpad)作为端基配体,合成了2个同构化合物[{Ni(cpad)}₃M(CN)₆]₂[M(CN)₆](ClO₄)₃·6H₂O (M=Cr³⁺,1;Fe³⁺,2),其中[M(CN)₆]^3-通过氰基桥联配位,4个[Ni(cpad)]²⁺阳离子形成四核簇[{Ni(cpad)}₃M(CN)₆]³⁺,游离的[M(CN)₆]^3-和ClO₄^-为平衡阴离子。晶体参数如下：1,三方晶系,P3c1空间群,a=1.5144 1(18) nm,c=3.080 7(6) nm,V=6.118 9(15) nm³,Z=2;2,三方晶系,P3c1空间群,a=1.4976 2(17) nm,c=3.087 8(5) nm,V=5.997 6(14) nm³,Z=2。变温磁化率显示在四核簇内氰基桥联的金属离子之间存在铁磁相互作用。     

基于二氰根铬的一系列氰根桥联CrⅢ-CuⅡ-CrⅢ三核配合物的合成、结构与磁性

基于一系列二氰根铬与[Cu(cyclam)](ClO₄)₂反应合成了3个氰根桥联Cr^Ⅲ-Cu^Ⅱ-Cr^Ⅲ三核配合物[Cu(cyclam)][Cr(bpmb)(CN)₂]₂·4H₂O(1)(cyclam=1,4,8,11-四氮杂环十四,bpmb^2-=1,2-二(2-吡啶甲酰胺基)-4-甲基苯),[Cu(cyclam)][Cr(bpdmb)(CN)₂]₂(2)(bpdmb^2-=1,2-二(2-吡啶甲酰胺基)-4,5-二甲基苯)和[Cu(cyclam)][Cr(bpClb)(CN)₂]₂·4H₂O(3)(bpClb^2-=1,2-二(2-吡啶甲酰胺基)-4-氯苯)。单晶衍射结果表明:3个化合物是结构类似的中性三核配合物,均含有氰根桥联的Cr(Ⅲ)-CN-Cu(Ⅱ)-NC-Cr(Ⅲ)连接;磁性研究表明:氰根桥在Cr^Ⅲ和Cu^Ⅱ离子间传递弱的铁磁耦合作用,基于自旋哈密顿算符Ĥ=-2J_CrCuŜ_Cu(Ŝ_Cr1+Ŝ_Cr2)拟合得到它们的磁耦合常数分别是J_CrCu=1.53(2) cm^-1(1),0.45(1) cm^-1(2)和0.73(2) cm^-1(3)。     

乳酸类合成子构建的四连接螺旋手性配位聚合物的合成、结构和光催化性质

通过乳酸衍生物和3-溴-4-羟基苯甲酸的组合得到对映体3-溴-4-(((1R)-1-羧基乙基)氧基)苯甲酸(R-H₂bba)和3-溴-4-(((1S)-1-羧基乙基)氧基)苯甲酸(S-H₂bba)。以其为手性合成子在水热条件下分别与1,3-二(吡啶-4-基)丙烷(1,3-dpp)和Ni²⁺反应,构建了对映手性配位聚合物{[Ni(R-bba)(1,3-dpp)(H₂O)_0.5]·1.5H₂O}_n (HU12-R)和{[Ni(S-bba)(1,3-dpp)(H₂O)_0.5]·1.5H₂O}_n (HU12-S)。结构分析揭示HU12-R和HU12-S是具有dia网络特征的三维螺旋骨架。在骨架中,阴离子配体R-bba^2-和S-bba^2-分别与Ni²⁺中心连接在一起围绕2₁螺旋轴得到一对小的对映螺旋链,而1,3-dpp与Ni²⁺中心则围绕4₁螺旋轴构建出另外一对大的对映螺旋链。电化学测试显示HU12-R属n型半导体,具有低阻抗性质,对紫外可见光有很强的吸收能力。进一步光催化实验证实在紫外光照射下所得配合物对染料降解有明显催化效果。     

三种马来二腈基二硫烯镍(Ⅲ)离子对配合物的制备和结构表征

合成了3种离子对配合物 [1-benzyl-3-bromopyridium]⁺[Ni(mnt)₂]^- (1)，[1-(4′-flurobenzyl)-3-bromopyridiunm]⁺[Ni(mnt)₂]^- (2)，[1-(4′-cholorobenzyl)-3-bromopyridium]⁺[Ni(mnt)₂]^- (3)，(mnt=马来二腈基二硫烯，maleonitrile dithiolate)获得了单晶并解析了它们的单晶结构。     

3,6-二(N-咪唑/苯并咪唑基)哒嗪配体配合物的合成、结构、荧光及光催化性能

用溶剂热法设计、合成了4个金属-有机配合物[Mn(L¹)₄(OH)₂] (1),{[MnL¹(H₂O)₄]SO₄}_n (2),[CdL²(NO₃)₂]_n (3)和{[Co(L²)₂](PF₆)₂}_n (4),(L¹=3,6-二(N-咪唑基)哒嗪,L²=3,6-二(N-苯并咪唑基)哒嗪),并通过元素分析、红外、X射线单晶衍射对配合物结构进行了表征,测试结果表明配合物1具有单核结构,2为一维链结构,配合物3和4均为二维网状结构。此外,对配合物3和4的固态荧光性能及光催化的性能做了进一步研究。     

Synthesis, structures, and magnetic properties of a series of cyano-bridged Fe-Mn bimetallic complexes

The preparation and crystal structures of five cyano-bridged Fe-Mn complexes, [(bipy)2Fe(II)(CN)2Mn(II)(bipy)2]2(ClO4)4 (1), [(bipy)2Fe(II)(CN)2Mn(II)(DMF)3(H2O)]2(ClO4)4 (2), {[(Tp)Fe(III)(CN)3]2Mn(II)(DMF)2(H2O)}2 (3), {[(Tp)Fe(III)(CN)3]2Mn(II)(DMF)2}n (4), and Na2[Mn(II)Fe(II)(CN)6] (5) (bipy = 2,2'-bipyridine, Tp = tris(pyrazolyl)hydroborate), are reported here. Compounds 1-4 contain the basic Fe2(CN)4Mn2 square building units, of which 1-3 show the motif of discrete molecular squares of Fe2(CN)4Mn2 and 4 possesses a 1D double-zigzag chain-like structure, while compound 5 is a 3D cubic framework analogous to that of Prussian blue. Compounds 1 and 2 show weak ferromagnetic interactions between two Mn(II) ions through the bent -NC-Fe(II)-CN- bridges. Compound 3 shows weak antiferromagnetic coupling between the Fe(III) and Mn(II) ions, while compound 4 displays a metamagnetic-like behavior with TN = 5.2 K and Hc = 10.5 kOe. Compound 5 exhibits a ferromagnetic ordering with Tc= 3.5 K, coercive field, Hc, = 330 G, and a remnant magnetization of 503 cm3 Oe mol(-1).     

Hexanuclear Fe(III)2Co(III)2M(II)2 (M = Cu, Ni, Mn) clusters based on Kläui's tripodal ligand and tricyanometalates: syntheses, structures and magnetic properties

With the use of Kl?ui's tripodal ligand, [(Cp)Co(P(O)(OEt)(2))(3)](-) (L(CoEt), Cp = cyclopentadiene) as the auxiliary ligand to react with different metal salts and tricyanometalate building blocks, five neutral trimetallic hexanuclear complexes: [(Tp)(2)Fe(2)(CN)(6)Cu(2)(L(CoEt))(2)]·6H(2)O (1, Tp = hydridotris(pyrazolyl)borate), [(Tp*)(2)Fe(2)(CN)(6)Cu(2)(L(CoEt))(2)]·2H(2)O (2, Tp* = hydridotris(3,5-dimethyl-pyrazolyl)borate), [(pzTp)(2)Fe(2)(CN)(6)Cu(2)(L(CoEt))(2)]·H(2)O·3MeOH (3, pzTp = tetra(pyrazolyl)borate), [(Tp)(2)Fe(2)(CN)(6)Ni(2)(L(CoEt))(2)(MeCN)(2)]·2MeCN·2H(2)O (4) and [(Tp)(2)Fe(2)(CN)(6)Mn(2)(L(CoEt))(2)(MeCN)(2)]·2MeCN (5), have been obtained and structurally characterized. Magnetic measurements confirm that there are ferromagnetic couplings between the cyano-bridged Fe and Cu/or Ni ions and antiferromagnetic interaction between the cyano-bridged Fe and Mn ions. Slow relaxation of the magnetization is observed in complexes 1 and 4, while complex 3 exhibits metamagnetic behavior with a critical field of 17.5 kOe.     

Chiral cyanide-bridged Cr(III)-Mn(III) heterobimetallic chains based on [(Tp)Cr(CN)3]-: synthesis, structures, and magnetic properties

By the reactions of Mn(III) Schiff-base complexes with the tricyanometalate building block, [(Tp)Cr(CN)(3)](-) (Tp = Tris(pyrazolyl) hydroborate), two couples of enantiomerically pure chiral cyano-bridged heterobimetallic one-dimensional (1D) chain complexes, [Mn((R,R)-Salcy)Cr(Tp)(CN)(3)·1/4H(2)O·1/2CH(2)Cl(2)](n) (1) and [Mn((S,S)-Salcy)Cr(Tp)(CN)(3)·1/4H(2)O·1/2CH(2)Cl(2)](n) (2) (Salcy = N,N'-(1,2-cyclohexanediylethylene)bis(salicylideneiminato) dianion), [Mn((R,R)-Salphen)Cr(Tp)(CN)(3)](n) (3) and [Mn((S,S)-Salphen)Cr(Tp)(CN)(3)](n) (4) (Salphen = N,N'-1,2-diphenylethylene-bis(salicylideneiminato) dianion), have been successfully synthesized. Circular dichroism (CD) spectra confirm the enantiomeric nature of the optically active complexes. Structural analyses reveal the formation of neutral cyano-bridged zigzag single chains in 1 and 2, and neutral cyano-bridged zigzag double chains in 3 and 4. Magnetic studies show that antiferromagnetic couplings are operative between Cr(III) and Mn(III) centers bridged by cyanide. Complexes 1 and 2 are the rare examples of chiral ferrimagnets; while complexes 3 and 4 exhibit a coexistence of chirality and spin-glass behavior in a 1D chain.     

Pyrazolylborates and their importance in tuning single-molecule magnet properties of {Fe(III)2Ni(II)} complexes

A new tricyanoferrate(III) building block and a trinuclear single-molecule magnet derivative are described. The treatment of a 2:1 ratio of [NEt(4)][(Tp*(Bn))Fe(III)(CN)(3)]·H(2)O·MeOH [1; Tp*(Bn) = tris(3,5-dimethyl-4-benzyl)pyrazolylborate] with nickel(II) trifluoromethanesulfonate gives {[(Tp*(Bn))Fe(III)(CN)(3)](2)[Ni(II)(DMF)(4)]}·2DMF (2; DMF = N,N-dimethylformamide). The symmetry-equivalent Fe(III)(LS) ions lead to a favorable alignment of anisotropy tensors (i.e., Fe···B axes) in 2, and an energy barrier of Δ(eff)/k(B) = 16.7 K is found for the S(T) = 2 complex.     

D,L-1,2,2-三甲基环戊烷-1,3-二胺硝酸镍配合物的合成、结构及其和手性D-(+)-1,2,2-三甲基环戊烷-1,3-二胺氯化镍配合物的对比分析

0IntroductionAsweknow,camphoricderivativespossessingtwochiralcarbonatomsintheirmoleculesoccupyalargebranchoforganiccompoundsandhavebeenusedwidelyinorganicsynthesis.D鄄,L鄄andD,L鄄1,2,2鄄trimethylcyclopentane鄄1,3鄄diaminesareveryusefulintermediatesinorgan     

Single-molecule magnets constructed from cyanometalates: {[Tp*Fe(III)(CN)3M(II)(DMF)4]2[OTf]2} x 2DMF (M(II) = Co, Ni)

Treatment of several divalent transition-metal trifluoromethanesulfonates [M(II)(OTf)2; M(II) = Mn, Co, Ni] with [NEt4][Tp*Fe(III)(CN)3] [Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate] in DMF affords three isostructural rectangular clusters of {[Tp*Fe(III)(CN)3M(II)(DMF)4]2[OTf]2} x 2DMF (M(II) = Mn, 3; Co, 4; Ni, 5) stoichiometry. Magnetic studies of 3-5 indicate that the Tp*Fe(CN)3(-) centers are highly anisotropic and exhibit antiferromagnetic (3 and 4) and ferromagnetic (5) exchange to afford S = 4, 2, and 3 spin ground states, respectively. ac susceptibility measurements suggest that 4 and 5 exhibit incipient single-molecule magnetic behavior below 2 K.     

基于[(Tp)Fe(CN)3]-氰根桥联异金属三核配合物的合成、晶体结构及磁性

采用[(Tp)Fe(CN)3]-(Tp=hydrotris(pyrazolyl)borate)与[NiL](ClO4)2(L=3,10-bis(2-bydroxyethyl)-1,3,5,8,10,12-hexaazacyclotetra-decane)反应,合成了氰根桥联的异金属三核配合物[NiL][(Tp)Fe(CN)3]2·4H2O(1),并对其结构和磁性进行了研究.该化合物晶体属于正交晶系,Pbca空间群.配合物1中,Ni(Ⅱ)大环与2 [(Tp)re(CN)3]-通过氰根桥联,形成近似直线的三核结构.Ni原子的配位采取六配位稍畸变的八面体构型.其中大环配体上的4个N原子占据赤道平面而桥联氰根的2个N原子占据轴向位置.磁性测定表明在2-300 K的温度范围内,Ni(Ⅱ)和Fe(Ⅲ)之间通过桥联的氰根产生弱的铁磁相互作用.用哈密顿函数H=-2J(SFel·SNi SFe2·SNi)对其XMT-T曲线进行了拟合,得到1的朗德因子g=2.35和交换常数J=8.13 cm-1.最后,对配合物的结构与磁性的关系进行了讨论.     

Assembly of azido- or cyano-bridged binuclear complexes containing the bulky [Mn(phen)2]2+ building block: syntheses, crystal structures, and magnetic properties

Two new cyano-bridged heterobinuclear complexes, [Mn(II)(phen)2Cl][Fe(III)(bpb)(CN)2] x 0.5CH3CH2OH x 1.5H2O (1) and [Mn(II)(phen)2Cl][Cr(III)(bpb)(CN)2] x 2H2O (2) [phen = 1,10-phenanthroline; bpb(2-) = 1,2-bis(pyridine-2-carboxamido)benzenate], and four novel azido-bridged Mn(II) dimeric complexes, [Mn2(phen)4(mu(1,1)-N3)2][M(III)(bpb)(CN)2]2 x H2O [M = Fe (3), Cr (4), Co (5)] and [Mn2(phen)4(mu(1,3)-N3)(N3)2]BPh4 x 0.5H2O (6), have been synthesized and characterized by single-crystal X-ray diffraction analysis and magnetic studies. Complexes 1 and 2 comprise [Mn(phen)2Cl]+ and [M(bpb)(CN)2]- units connected by one cyano ligand of [M(bpb)(CN)2]-. Complexes 3-5 are doubly end-on (EO) azido-bridged Mn(II) binuclear complexes with two [M(bpb)(CN)2]- molecules acting as charge-compensating anions. However, the Mn(II) ions in complex 6 are linked by a single end-to-end (EE) azido bridging ligand with one large free BPh4(-) group as the charge-balancing anion. The magnetic coupling between Mn(II) and Fe(III) or Cr(III) in complexes 1 and 2 was found to be antiferromagnetic with J(MnFe) = -2.68(3) cm(-1) and J(MnCr) = -4.55(1) cm(-1) on the basis of the Hamiltonian H = -JS(Mn)S(M) (M = Fe or Cr). The magnetic interactions between two Mn(II) ions in 3-5 are ferromagnetic in nature with the magnetic coupling constants of 1.15(3), 1.05(2), and 1.27(2) cm(-1) (H = -JS(Mn1)S(Mn2)), respectively. The single EE azido-bridged dimeric complex 6 manifests antiferromagnetic interaction with J = -2.29(4) cm(-1) (H = -JS(Mn1)S(Mn2)). Magneto-structural correlationship on the EO azido-bridged Mn(II) dimers has been investigated.     

Cyano-bridged pentanuclear Fe(III)3M(II)2 (M = Ni, Co, Fe) clusters: synthesis, structures, and magnetic properties

The reactions of [M(II)(Tpm(Me))(H2O)3]2+ (M = Ni, Co, Fe; Tpm(Me) = tris(3,5-dimethyl-1-pyrazoyl)methane) with [Bu4N][(Tp)Fe(III)(CN)3] (Bu4N+ = tetrabutylammonium cation; Tp = tris(pyrazolyl)hydroborate) in MeCN-Et2O afford three pentanuclear cyano-bridged clusters, [(Tp)3(Tpm(Me))2Fe(III)3M(II)2(CN)9]ClO4.15H2O (M = Ni, 1; M = Co, 2) and [(Tp)3(Tpm(Me))2Fe(III)3Fe(II)2(CN)9]BF4.15H2O (3). Single-crystal X-ray analyses reveal that they show the same trigonal bipyramidal structure featuring a D3h-symmetry core, in which two opposing Tpm(Me)-ligated M(II) ions situated in the two apical positions are linked through cyanide bridges to an equatorial triangle of three Tp-ligated Fe(III) (S = 1/2) centers. Magnetic studies for complex 1 show ferromagnetic coupling giving an S = 7/2 ground state and an appreciable magnetic anisotropy with a negative D(7/2) value equal to -0.79 cm(-1). Complex 2 shows zero-field splitting parameters deducted from the magnetization data with D = -1.33 cm(-1) and g = 2.81. Antiferromagnetic interaction was observed in complex 3.