无机化学（张天蓝）cu

Chap21.CopperEnzymeFunctionConsequencesofdeficiencyCuZnsuperoxidedismutaseFreeradicaldetoxicationOxidativedamageofcellcomponentsCytochromecoxidaseElectrontransportinthemitochondriaSymptomsofdeficiencyofATP:myopathy,ataxia,selzuresCeruloplasmin（铜蓝蛋白）CopperandirontransportIronaccumulationandneurologicaldamagePeptidylglycineMonooxygenaseBioactivationofpeptidehormonesProbablewidespreadeffectsthroughmalfunctionofseveralpeptidehormonesTyrosinase（酪氨酸酶）FormationofmelaninHypopigmentationClottingFactor,V,VIIIBloodclottingBleedingtendencyΒ-amyloidprecursorproteinNormalfunctioncurrentlyunknownFamilialAlzheimer’sdeseaseBiologicalfunctionofCopper★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；本章教学要求铜副族元素在周期表中的位置CopperSilverGoldSimplysubstances性质增加铜原子量29电子构型3d104s1氧化态+I,+II电离能(kJ/mol-1)第一745.3电离能(kJ/mol-1)第二1957.3有效半径M+/pm77M2+/pm73M+（g)水化能/kJ.mol-1-582M2+（g)水化能/kJ.mol-1-2121电负性1.9GeneralpropertyWhycuprous（亚铜离子）can’tbestableinwater？

主要是Cu2+的水合能(-2119kJ·mol-1)比Cu+(-581kJ·mol-1)大得多，由Cu+变成Cu2+增加的水合能可以补偿由Cu+变成Cu2+所消耗的第二电离能(1958kJ·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ΔrH=-85kJ·mol-1，Kθ

=1.7×106，自然该歧化反应易于进行.Question

Sodiumionsurroundedbywater,attractedbyelectrostaticattractionCopperion,physicallybondedtowaterHydration、Polymerizeandprecipitationofcupricions也是配合物Hydration五水硫酸铜的TG（a）和DTG（b）对[Cu(H2O)4]SO4·H2O结构的解释有两种：[Cu(H2O)4SO4]·H2O结构的另一种解释theartist，

2008,

RogerHiornsAtomicRadiiOfTheTM’sElements3d104s1过渡元素原子半径：同一周期,从左→右r↓ⅦB,Ⅷ最小,然后↑未充满,d的屏蔽效应↓、z↑、r↓.到了ⅡB全充满d屏蔽↑、z↓、r↑[Cu(H2O)4]2+⇌[Cu(H2O)3(OH)]+

＋H+

hydrolysis

logKa=-7.22precipitation

浅蓝深蓝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、PolymerizeandprecipitationofcuprousionsOxidationIsLosingelectronsOXIDATIONandREDUCTIONReductionIsGainingelectronsXm+Xm2+e-oxidizedreducede-ElectronacceptorElectrondonorRedoxactive(Transition)metals(copper/ironcontainingproteins)OXIDATIONandREDUCTIONCu2+Cu+Cu00.1590.5210.337EACu2+CuCl

Cu0

0.5380.137Cl-

Cu(0H)2Cu2O

Cu0-0.08-0.361EBCu(I)/Cu(II)转化的影响

Cu2++e→Cu+E=0.159V2Cu2++2I-=2Cu++I2

Cu(II)+e—→Cu(I)

E=0.159V

或/和沉淀剂Cu(I)

难溶化合物或/和络合剂Cu(I)

稳定配合物(Dependenceofpotentialoncomplexationandprecipitation)I2+e→I-E=0.535V2Cu2+(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

[Cu2+]=E

（Cu2+/Cu+）+———lg——1[Cu+]1=E

（Cu2+/Cu+）+0.059lg——Ksp,CuI

E

（Cu2+/Cu+）=0.159VEø

I2/I-=+0.535V2Cu2+(aq)+5I-(aq)═══2CuI(s)+I3-(aq)+Na2S2O3(aq)

I-+S4O62-

E

（Cu2+/CuI）=0.828V>E

(I2/I-)=0.535V

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

Question

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+=0.521-0.152=0.369V

nE

1×0.369lgK=————=————=6.239

0.059140.05914

[Cu2+]

K=————=1.73×106

[Cu+]2Disproportionation(岐化)ofCu(I)Cu2+Cu+Cu0.5210.3370.152Cu(I)

+H2O2

Cu(II)+

OH+OH–

k=4.7x103

M-1s-1Theformation,transformationandeliminateofReactiveoxygenspecies铜离子catalyze的Fenton反应Cu2++e→Cu+

E

=0.152V

H2O2+e

·OH+OH－

E

=0.90VEH2O/·

OH=2.31V,·OH有极强的氧化能力，几乎以109～1010mol/L/sec的速度与所有有机分子反应Theformation,transformationandeliminateofReactiveoxygenspeciesH2O2Cu+O2·OH+OH-Cu2+·O2－Haber-Weisz反应·O2-+H2O2⇌O2+·OH+OH-Cuee铜离子catalyze的Haber-Weisz反应E(v)0.900.152-0.33BleomycinisaDNAcleavingantibioticandanti-cancerdrugMetalbindingsiteGlyco-peptidepartthatsitsintheminorgrooveIntercalatesintoDNA博莱霉素(bleomycin，BLM）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·CheckPoint

请总结类Haber-Weisz反应发生的条件.EA0O2HO2.H2O2-0.130.89EB0O2O2.-H2O2-0.56-0.41E右>E左铜离子catalyze的.O2.-Disproportionation反应2•O2-+2H+=1O2+H2O2

（≤0.4M-1•sec）WildTypeSODJesseFitzpatrick(2008)Dr.Beckman’sLabTheLinusPaulingInstituteO2-O2Cu2+Cu1+Cu,ZnSODCu,ZnSODZnZnCu2+Cu2+e-O2-H2O2铜离子catalyze的O2.-Disproportionation反应k=~8x109

M-1s-1k=~1010

M-1s-1Netreaction:O2

–

+O2

–

+2H+H2O2+O2

Cuinvivoishowever10,000×catalysedbysuperoxidedismutase(SOD)铜离子带正电,一方面结合超氧离子，一方面传递电子Netreaction:O2

–

+O2

–

+2H+H2O2+O2

CuCopperparticipatesinreactionsreactiveoxygenspecies(ROS)producingreactions:LipidperoxidationOxidationofproteinsCu+Cu2+CopperisapotentcytotoxinwhenaccumulatesinexcessComplexationofcupricandcuprous配合物：CuCl2-,CuBr2-,CuI2-,Cu(SCN)2-,Cu(CN)2-Cu(I)的配合物多为2配位Kf大小浅蓝深蓝浅蓝深蓝浅蓝蓝H2OCu(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)04p1

↑σ

↑σ

↑σ

↑σNH3NH3NH3NH3Cu(NH3)42+稳定，不显还原性，说明“杂化轨道法”有缺陷。例2:[Cu(CN)4]3-

正四面体

sp3杂化

Cu+

3d10

—————→3d10

(sp3)0(sp3)0(sp3)0(sp3)0

↑σ

↑σ↑σ

↑σCN-CN-CN-CN-Jahn-Tellereffect"anynon-linearmolecularsysteminadegenerateelectronicstatewillbeunstableandwillundergodistortiontoformasystemoflowersymmetryandlowerenergytherebyremovingthedegeneracy"Cu(II)的6配位配合物Cu(H2O)62+、CuF64–、[Cu(NH3)4(H2O)2]2+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Thed-orbitals:the

t2gsetthe

egsetdyzdxydxzdz2dx2-y2xxxxxzzzzzyyyyyRecall:Splittingofthedsub-shellinoctahedralcoordinationdyzdz2dx2-y2thethreeorbitalsofthe

t2gsetliebetweentheliganddonor-atoms(onlydyzshown)thetwoorbitalsoftheegsetliealongtheCartesiancoordinates,andsoareadjacenttothedonoratomsoftheligands,whichraisestheeg

setinenergyzzzblue=liganddonoratomorbitalsthe

egsetthe

t2gsetyyyxxxCrystalFieldStabilizationEnergy(CFSE):d-shellsplitbypresenceofliganddonor-atoms

CFSE=Δ{0.4n(t2g)-0.6n(eg)}n(t2g)andn(eg)arethenumbersofelectronsin thet2gandeglevelsStructuraleffectsofJahn-TellerdistortiontwolongaxialCu-Obonds=2.45Å[Cu(H2O)6]2+J-TdistortionlengthensaxialCu-O’s[Ni(H2O)6]2+noJ-Tdistortionfourshortin-planeCu-Obonds=2.00ÅAllsixNi-Obondsequalat2.05Å

TheJahn-TellerTheoremegegegt2gt2gd8t2gHigh-spinNi(II)–onlyonewayoffillingtheeglevel–notdegenerate,noJ-TdistortionenergyCu(II)–twowaysoffillingeglevel–itisdegenerate,andhasJ-Tdistortiond9Ni(II)压扁的八面体Cu2+3d9

t2g6(dz2)1(dx2－y2)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,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(dx2－y2)1,由于dx2－y2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。

ForM(II)ionswiththesamesetofligands,thevariationofΔisnotlarge.OnecanthereforeusetheequationforCFSEtocalculateCFSEintermsofΔford0throughd10M(II)ions(allmetalionshigh-spin):

Ca(II)Sc(II)Ti(II)V(II)Cr(II)Mn(II)Fe(II)Co(II)Ni(II)Cu(II)Zn(II)

d0d1d2d3d4d5d6d7d8d9d10CFSE:00.4Δ0.8Δ1.2Δ0.6Δ

00.4Δ0.8Δ1.2Δ0.6Δ

0

CrystalFieldStabilizationEnergy(CFSE)ofd0tod10M(II)ions:

CFSE=Δ{0.4n(t2g)-0.6n(eg)}CrystalFieldStabilizationEnergy(CFSE)ofd0tod10M(II)ions:Ca2+Mn2+Zn2+double-humpedcurveNi2+LogK1(en)ofd0tod10M(II)ions:double-humpedcurveCa2+Mn2+Zn2+risingbaselineduetoioniccontraction=CFSECu2+Cr2+TheIrving-Williamsseries

Mn2+<Fe2+<Co2+<Ni2+

<Cu2+>Zn2+TheorderisrelativelyinsensitivetothechoiseofligandsTheseriesreflectselectrostaticeffects.However,beyondMn2+thereisasharpincreaseinthevalueofKfforFe(II),d6,Co(II),d7,Ni(II)d8,andCu(II)d9.TheseionsexperinceanadditionalstabilizationproportionaltotheLFSE.TetragoanallydistortedCu(II)enhancesthestabilizationofcomp.TheIrving-WilliamsStabilityOrder:Ar3d4sFeatomAr3d4sFe2+(Ferrous)Ar3d4sFe3+(Ferric)Ar3d4sCuatomAr3d4sCu+(cuprous)Ar3d4sCu2+(cupric)SimilarityanddifferencesbetweenCu&Fe3d104s13d64s2

Coordinationatom:

Fe3+-

Hardacid

O>N

Cu2+，

Fe2+-

mediaacid

N>S>O

Cu+-softacid

S,CN-,X-

Coordinationnumber：

Cu+

2,4

如[CuI2]+sp,[Cu(CN)4]3-sp3Cu2+4,6

如[Cu(NH3)4]2+

dsp2[Cu(NH3)4H2O）2]2+

sp3d2Fe2+,Fe3+6

如[Fe(CN)6]4-,[Fe(CN)6]3-d2sp3

Cu(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.ImportantforredoxchemistryCu(II)+e‾Cu(I)UnregulatedredoxisdangerousFentonChemistryCu++H2O2Cu2++HO‾+HO•OxidativeStress!CopperinHumanHealthNeurologicalfunction

(dopamineβhydroxylase)Connectivetissueformation

(lysyloxidase)Ironmetabolism

(ceruloplasmin)Oxidativephosphorylation

(cytochromeC-oxidase)Antioxidantactivity

(Cu/Znsuperoxidedismutase)Pigmentation

(tyrosinase)Waggoner,Neurobiol.ofDisease,1999,6,2212CopperinHumanDiseaseNeurologicalfunction

(dopamineβhydroxylase)Connectivetissueformation

(lysyloxidase)Ironmetabolism

(ceruloplasmin)Oxidativephosphorylation

(cytochromeC-oxidase)Antioxidantactivity

(Cu/