无机化学张天蓝cu

1、Chap21. Copper,Biological function of Copper,掌握溶液中铜离子的水解，聚合和沉淀 掌握溶液中铜离子的氧化还原及其生物效应 掌握溶液中铜离子的配位化学及其生物效应 了解铜在生物体内的性质和功能；,铜副族元素在周期表中的位置,Copper,Silver,Gold,Simply substances,General property,Why cuprous（亚铜离子） cant be stable in water？,主要是 Cu2+的水合能 (- 2119 kJ mol-1) 比 Cu+ (-581 kJ mol-1) 大得多，由 Cu+ 变成 Cu2+

2、 增加的水合能 可以补偿由 Cu+ 变成 Cu2+ 所消耗的第二电离能 (1958 kJ mol-1) ，因此水溶液中 Cu2+比 Cu+ 更稳定 . 歧化反应： 2Cu+(aq) 2Cu2+(aq) + Cu(s) 的 r H = - 85 kJ mol-1， K = 1.7 106，自然该歧化反应 易于进行 .,Question,Sodium ion surrounded by water, attracted by electrostatic attraction,Copper ion, physically bonded to water,Hydration、Polymerize an

3、d precipitation of cupric ions,也是配合物,Hydration,五水硫酸铜的TG（a）和DTG（b）,对Cu(H2O)4SO4H2O结构的解释有两种：,Cu(H2O)4SO4H2O 结构的另一种解释,the artist， 2008, Roger Hiorns,Atomic Radii Of The TMs Elements,3d104s1,过渡元素原子半径：同一周期, 从左右 r B , 最小 , 然后未充满,d的屏蔽效应、z、r.到了B全充满d屏蔽、z 、 r,Cu(H2O)42+ Cu(H2O)3(OH)+ H+,hydrolysis,logKa= -7.2

4、2,precipitation,氢氧化铜和氢氧化铁（III）一样有轻微的两性,检验糖尿病：红色为有病，蓝色没有病,Hydration、Polymerize and precipitation of cuprous ions,Oxidation Is Losing electrons,OXIDATION and REDUCTION,Reduction Is Gaining electrons,Xm+ Xm2+,e-,oxidized,reduced,e-,Electron acceptor,Electron donor,OXIDATION and REDUCTION,Cu2+ Cu+ Cu0,0

5、.159,0.521,EA,Cu2+ CuCl Cu0,0.538,0.137,Cl-,Cu(0H)2 Cu2O Cu0,Cu(I)/ Cu(II)转化的影响,Cu2+ +e Cu+ E=0.159V,2Cu2+ +2I- = 2 Cu+ +I2,(Dependence of potential on complexation and precipitation),I2+e I- E= 0.535V,2Cu2+(aq) + 5I-(aq) 2CuI(s) + I3-(aq),碘量法测定Cu2+的含量(间接法）,E （Cu2+/CuI ）= E（Cu2+/Cu+）,= 0.828V,0.059

6、Cu2+ = E （Cu2+/Cu+）+ lg 1 Cu+,1 = E （Cu2+/Cu+）+ 0.059 lg Ksp,CuI,E （Cu2+/Cu+）= 0.159V E I2/I- = + 0.535 V,2Cu2+(aq) + 5I-(aq) 2CuI(s) + I3-(aq) + Na2S2O3(aq) I- + S4O62-,E （Cu2+/CuI ） = 0.828V E (I2/I- ) = 0.535 V E池 0, 自发,产物是 Cu(I) 的难溶盐时， Cu(II)有较好的氧化性。,碘量法(Iodometry,利用的I2氧化性和 I-的还原性为基础的一种氧化还原方法,Qu

7、estion,设计一个试验：用碘量法（滴定碘法 ）测定样品中葡萄糖浓度,在待测样品中加入已知过量的Cu2+使葡萄糖与Cu2+充分作用，然后加入KI使它与剩余的Cu2+作用，生成的单质碘的量反映剩余的Cu2+的量，加入淀粉时溶液变蓝，然后用硫代硫酸钠溶液滴定直到蓝色消失。就可以根据消耗的硫代硫酸钠计算与葡萄糖作用的铜的浓度，再计算葡萄糖的浓度。,Solution,Cu2+ + e Cu+ E Cu2+/Cu+ = 0.152V Cu+ + e Cu E Cu+/Cu = 0.521V 2Cu+ = Cu2+ + Cu(s),E池 = E Cu+/Cu - E Cu2+/Cu+= 0.521 -

8、0.152= 0.369 V,n E 10.369 lgK = = = 6.239 0.05914 0.05914,Cu2+ K = = 1.73106 Cu+2,Disproportionation(岐化)of Cu(I),Cu(I) + H2O2 Cu(II) + OH + OH,k = 4.7 x 103 M-1 s-1,The formation, transformation and eliminate of Reactive oxygen species,铜离子catalyze 的Fenton反应,Cu2+ + e Cu+ E= 0.152V,H2O2+e OH + OH E= 0

9、.90V,E H2O/ OH=2.31V, OH有极强的氧化能力， 几乎以1091010mol/L/sec的速度与所有有机分子反应,The formation, transformation and eliminate of Reactive oxygen species,H2O2 Cu+ O2 OH + OH- Cu2+ O2,e,e,铜离子catalyze 的Haber-Weisz反应,E(v) 0.90 0.152 -0.33,Bleomycin is a DNA cleaving antibiotic and anti-cancer drug,博莱霉素 (bleomycin，BLM）,

10、Cu,导致DNA链的断裂原因是由于博来霉素分子的一部分是铁或铜的配合物，这类配合物能够产生导致DNA链断裂的自由基。,CuP-3A的配位结构示意图,博莱霉素的活性中心,Check Point 请总结类Haber-Weisz反应发生的条件,.,EA0 O2 HO2 . H2O2,-0.13,0.89,EB0 O2 O2 .- H2O2,-0.56,-0.41,E右E左,铜离子catalyze 的. O2.- Disproportionation反应,2 O2-+2H+ = 1O2+ H2O2 （0.4 M-1 sec）,Wild Type SOD,Jesse Fitzpatrick (2008)

11、 Dr. Beckmans Lab The Linus Pauling Institute,O2-,O2,Cu2+,Cu1+,Cu, Zn SOD,Cu, Zn SOD,e-,O2-,H2O2,铜离子catalyze 的O2 .- Disproportionation反应,k = 8 x 109 M-1 s-1,k = 1010 M-1 s-1,Net reaction: O2 + O2 + 2H+ H2O2 + O2,Cu,in vivo is however 10,000 catalysed by superoxide dismutase (SOD),铜离子带正电, 一方面结合超氧离子，一

12、方面传递电子,Net reaction: O2 + O2 + 2H+ H2O2 + O2,Cu,Copper participates in reactions reactive oxygen species (ROS) producing reactions :,Cu+,Cu2+,Copper is a potent cytotoxin when accumulates in excess,Complexation of cupric and cuprous,配合物：CuCl2-,CuBr2-,CuI2-,Cu(SCN)2-,Cu(CN)2-,Cu(I)的配合物多为2配位,Kf,大,小,Cu

13、(II)的配合物多为4配位,dsp2杂化,配合物的杂化成键过程,例1：Cu(NH3)42+ 的杂化成键 Cu(NH3)42+正方形 Cu2+ 3d9 3d84p1 3d8(dsp2)0(dsp2)0(dsp2)0(dsp2)0 4p1, NH3 NH3 NH3 NH3,Cu(NH3)42+稳定，不显还原性，说明“杂化轨道法”有缺陷。,例2: Cu(CN)43- 正四面体,sp3杂化 Cu+ 3d10 3d10 (sp3)0(sp3)0(sp3)0 (sp3)0, CN- CN- CN- CN-,Jahn-Teller effect,any non-linear molecular system

14、 in a degenerate electronic state will be unstable and will undergo distortion to form a system of lower symmetry and lower energy thereby removing the degeneracy,Cu(II)的6配位配合物,Cu(H2O)62+、 CuF64、Cu(NH3)4(H2O)22+,电子在简并轨道中的不对称占据会导致分子的几何构型发生畸变, 从而降低分子的对称性和轨道的简并度, 使体系的能量进一步下降, 这种效应称为姜泰勒效应,The d-orbitals

15、:,the t2g set,the eg set,dyz,dxy,dxz,dz2,dx2-y2,x,x,x,x,x,z,z,z,z,z,y,y,y,y,y,Recall:,Splitting of the d sub-shell in octahedral coordination,dyz,dz2,dx2-y2,the three orbitals of the t2g set lie between the ligand donor-atoms (only dyz shown),the two orbitals of the eg set lie along the Cartesian co

16、ordinates, and so are adjacent to the donor atoms of the ligands, which raises the eg set in energy,z,z,z,blue = ligand donor atom orbitals,the egset,the t2g set,y,y,y,x,x,x,Crystal Field Stabilization Energy (CFSE):,d-shell split by presence of ligand donor-atoms,CFSE =0.4n(t2g) -0.6n(eg),n(t2g) an

17、d n(eg) are the numbers of electrons inthe t2g and eg levels,Structural effects of Jahn-Teller distortion,two long axial Cu-O bonds = 2.45 ,Cu(H2O)62+ J-T distortion lengthens axial Cu-Os,Ni(H2O)62+ no J-T distortion,four short in-plane Cu-O bonds = 2.00 ,All six Ni-O bonds equal at 2.05 ,The Jahn-T

18、eller Theorem,eg,eg,eg,t2g,t2g,d8,t2g,High-spin Ni(II) only one way of filling the eg level not degenerate, no J-T distortion,energy,Cu(II) two ways of filling eg level it is degenerate, and has J-T distortion,d9,Ni(II),压扁的八面体,Cu2+ 3d9,t2g6(dz2)1(dx2y2)2 由于dz2轨道上缺少一个电子, 在z轴上d电子对中心离子的核电荷的屏蔽效应比在xy平面的小

19、, 中心离子对 z轴 方向上的两个配体的吸引就大于对xy平面上的四个配体的吸引, 从而使z轴方向上两个键缩短, xy面上的四条键伸长, 成为压扁的八面体,拉长的八面体,t2g6(dz2)2(dx2y2)1, 由于dx2y2轨道上电子比dz2轨道上的电子少一个, 则在xy平面上d电子对中心离子核电荷的屏蔽作用就比在z轴上的屏蔽作用小, 中心离子对xy平面上的四个配体的吸引就大于对z轴上的两个配体的吸引, 从而使xy平面上的四个键缩短, z轴方向上的两个键伸长, 成为拉长的八面体。,For M(II) ions with the same set of ligands, the variation

20、 of is not large. One can therefore use the equation for CFSE to calculate CFSE in terms of for d0 through d10 M(II) ions (all metal ions high-spin): Ca(II) Sc(II) Ti(II) V(II) Cr(II) Mn(II) Fe(II) Co(II) Ni(II) Cu(II) Zn(II) d0 d1 d2 d3 d4 d5 d6 d7 d8 d9 d10 CFSE: 0 0.4 0.8 1.2 0.6 0 0.4 0.8 1.2 0.

21、6 0,Crystal Field Stabilization Energy (CFSE) of d0 to d10 M(II) ions:,CFSE =0.4n(t2g) -0.6n(eg),Crystal Field Stabilization Energy (CFSE) of d0 to d10 M(II) ions:,Ca2+,Mn2+,Zn2+,double- humped curve,Ni2+,Log K1(en) of d0 to d10 M(II) ions:,double- humped curve,Ca2+,Mn2+,Zn2+,rising baseline due to

22、ionic contraction,= CFSE,Cu2+,Cr2+,The Irving-Williams series Mn2+ Zn2+ The order is relatively insensitive to the choise of ligands,The series reflects electrostatic effects. However, beyond Mn2+ there is a sharp increase in the value of Kf for Fe(II), d6, Co(II), d7, Ni(II) d8,and Cu(II) d9. These

23、 ions experince an additional stabilization proportional to the LFSE. Tetragoanally distorted Cu(II) enhances the stabilization of comp.,The Irving-Williams Stability Order:,Ar,3d,4s,Fe atom,Ar,3d,4s,Fe2+ (Ferrous),Ar,3d,4s,Fe3+ (Ferric),Ar,3d,4s,Cu atom,Ar,3d,4s,Cu+ (cuprous),Ar,3d,4s,Cu2+ (cupric)

24、,Similarity and differences between Cu&Fe,3d104s1,3d64s2,Coordination atom: Fe3+- Hard acid ON Cu2+， Fe2+ - media acid NSO Cu+-soft acid S, CN-, X- Coordination number： Cu+ 2, 4 如CuI 2+ sp, Cu(CN)43- sp3 Cu2+ 4, 6 如 Cu(NH3)42+ dsp2 Cu(NH3)4H2 O）22+ sp3d2 Fe2+, Fe3+ 6 如 Fe(CN)64-, Fe(CN)63- d2sp3 Cu(

25、I)和Fe(II)一样都可以与O2、CO等小分子配位结 合，形成反馈键 .,Important for redox chemistry Cu(II) + e Cu(I) Unregulated redox is dangerous,Fenton Chemistry Cu+ + H2O2 Cu2+ + HO + HO Oxidative Stress!,Copper in Human Health,Neurological function(dopamine hydroxylase),Connective tissue formation(lysyl oxidase),Iron metaboli

26、sm(ceruloplasmin),Oxidative phosphorylation(cytochrome C-oxidase),Antioxidant activity (Cu/Zn superoxide dismutase),Pigmentation(tyrosinase),Waggoner, Neurobiol. of Disease, 1999, 6, 221,2,Copper in Human Disease,Neurological function(dopamine hydroxylase),Connective tissue formation(lysyl oxidase),

27、Iron metabolism(ceruloplasmin),Oxidative phosphorylation(cytochrome C-oxidase),Antioxidant activity (Cu/Zn superoxide dismutase),Pigmentation(tyrosinase),Amyotrophic Lateral Sclerosis (ALS)1 SOD1 mutation enhances free radical generation by Cu Alzheimers Disease2 Cu may promote A aggregation Prion Disease3 Cu-binding to prion protein enhances protease stability 1. Rasia, PNAS, 2005, 102(12), 4294. 2. Bush, PNAS, 2003, 100(20), 11193. 3. Sigurdsson, J. Biol. Chem., 2003, 278(47), 46199,Waggoner, Neurobiol. of Disease, 1999, 6,