電化學選擇性氫化脫氯反應

關于電化學選擇性氫化脫氯反應第1頁，講稿共26頁，2023年5月2日，星期三目錄1.銀、鈀催化的電化學選擇性氫化脫氯反應簡介2.多氯吡啶甲酸的電化學選擇性氫化脫氯反應3.其他多氯有機物的電化學選擇性氫化脫氯反應4.總結(jié)和展望ZhejiangUniversityofTechnology2第2頁，講稿共26頁，2023年5月2日，星期三1.銀、鈀催化的電化學選擇性氫化脫氯反應簡介有機合成：合成部分氯代有機物作為藥物中間體或原料藥；要求:區(qū)域選擇性脫氯。1.1.主要用途及要求ZhejiangUniversityofTechnologyRondininiS.,etal.ElectroreductionofHalogenatedOrganicCompounds,2010,279;AlonaoF.,etal.Chem.Rev.,2002,102(11):4009-4091.環(huán)境保護：降解環(huán)境中存在的高毒、難降解氯代有機物；要求：化學選擇性脫氯。3第3頁，講稿共26頁，2023年5月2日，星期三1.2.催化原理IsseA.A.,etal.J.Phys.Chem.C,2009,113:14983;WangA.,etal.J.Am.Chem.Soc.:2010,132:9534.DaboP.,etal.Environ.Sci.Technol.,2000,34:1265;ChenG.,etal.J.Phys.Chem.B,2006,110:4863.Fig.1.1ThehydrodechlorinationmechanismonsilverelectrodeFig.1.2Thehydrodechlorinationmechanismonpalladiumelectrode4第4頁，講稿共26頁，2023年5月2日，星期三2.多氯吡啶甲酸的電化學選擇性氫化脫氯化工學報,2010,61:699.ZhejiangUniversityofTechnology5第5頁，講稿共26頁，2023年5月2日，星期三Fig.2.1CVsof3,5,6-T(a)

atfourelectrodesinaN2-saturated0.25MPBSatpH=3,

(b)ataAg(r)electrodeinaN2-saturated0.5MH2SO4(pH=0.2),a0.5MNaOH(pH=13.3)aqueoussolution,and0.25MPBSofthreedifferentpHvalues(3,7,and11);scanratev=50mVs-1,T=297K.Electrochim.Acta,2015,151:284;ZL201410264884.1ZhejiangUniversityofTechnology2.1.銀催化Ag(p)Ag(r)pH=3Ag(r)6第6頁，講稿共26頁，2023年5月2日，星期三Table2.1Electrochemicalreductionof3.33mM3,5,6-TinaN2-saturated0.5MH2SO4(pH=0.2),a0.5MNaOH(pH=13.3)aqueoussolution,and0.25MPBSofthreedifferentpHvalues(3,7,and11)at297Konfivecathodes.EntryCathodesIappaorEappaSolutionpHFinalproductdistribution(%)Currentefficiency(%)b3,5-Dselectivity(%)c3,6-Dselectivity(%)c3,5-D3,6-D3,5,6-T1Ni10mA30098.20002Cu10mA30098.50003Ag(p)1.0mA32.50.895.42.554.317.44GC1.0mA30094.40005Ag(r)10mA344.02.649.344.086.85.16Ag(r)-1.1V13.30.437.860.70.41.096.27Ag(r)-1.1V110.922.674.50.93.588.78Ag(r)-0.93V735.415.347.235.467.029.09Ag(r)-0.73V339.52.458.039.594.05.7010Ag(r)10mA0.20098.7000a2F·mol-1of3,5,6-Twereconsumedintheall10electrolysisexperiments.bCurrentefficiencycalculatedwithrespecttotheproduced3,5-D.c3,5-Dand3,6-Dselectivitycalculatedwithrespecttotheconverted3,5,6-T.ZhejiangUniversityofTechnology7第7頁，講稿共26頁，2023年5月2日，星期三Fig.2.2Productselectivityandcarbonmassbalanceduringtheelectrochemicalreductionof42.5mM3,5,6-Tat297K.Catholye:30mL0.25MPBSatpH=3.Cathode:Ag(r)meshelectrodes(2.5cm×3cm).ZhejiangUniversityofTechnologypH=3Ag(r)8第8頁，講稿共26頁，2023年5月2日，星期三ZhejiangUniversityofTechnologyFig.2.3EffectsofpHontheselectivityforhydrodechlorinationofTeCPonsilvercathodes.9第9頁，講稿共26頁，2023年5月2日，星期三Fig.2.5LSVofNifoam,Agmesh,Cufoamelectrodes,andPd/Nifoam,Pd/Agmesh,Pd/Cufoamelectrodesina0.5MNaOHaqueoussolution,v=5mV/s,withtwoconcentrationsof3,6-D,Temperature:25℃.Fig.2.4SEMofNiandPd/Nifoam,AgandPd/Agmesh,CuandPd/Cufoam.ZL201510401434.7;ZL201510401039.9.ZhejiangUniversityofTechnology2.2.鈀催化Pd/NifoamNifoamAgmeshCufoamPd/AgmeshPd/Cufoam10第10頁，講稿共26頁，2023年5月2日，星期三EntryCatholyte

pHFinalproductdistribution(%)CEc(%)3,6-DPA3-ClPA6-ClPA11.25MNaOH>14096.13.1087.220.25MNaOH11.5~13.5088.710.6084.030.5MKH2PO4+0.3MNaOH7.2~9.413.856.527.90.362.240.5MKH2PO4+0.2MNaOH4.4~6.647.336.417.60.240.550.5MKH2PO4+0.2MNaOH1.3~4.48.990.32.3081.76d

0.75MH2SO4+20%v/vEthanol<03.195.92.8086.9

Table2.2EffectofelectrolytecompositionontheECHdechlorinationof0.25M3,6-D.aaCathode:aPd/Nifoam(Projectedarea:2×6cm2,Pdloading:2.25mg/cm2).cCEwascalculatedwith△t=6h.d3,6-Dwasaddedintothecatholyteinadividedfashionduringthefirsthourofelectrolysisduetoitspoorsolubility.ZhejiangUniversityofTechnology11第11頁，講稿共26頁，2023年5月2日，星期三Fig.2.6

EffectofpHonproductselectivityandCEduringtheECHdechlorinationof3,6-D.Cathode:aPd/Nifoam;Catholyte:(AandA’)50mL1.25MNaOH+96mM3,6-D,andB’(B)50mL0.75MH2SO4+96mM3,6-D+20%v/vEthanol;CEwascalculatedwith△t=1,2,3,4,5or6.0h.ZhejiangUniversityofTechnology1.25MNaOH0.75MH2SO4

12第12頁，講稿共26頁，2023年5月2日，星期三Scheme1

ProposedmechanismsfortheECHdechlorinationof3,6-D.ZhejiangUniversityofTechnology13第13頁，講稿共26頁，2023年5月2日，星期三Fig.2.7EffectsofcathodecatalystsandpHontheselectivityforhydrodechlorinationofTeCP.ZhejiangUniversityofTechnology14第14頁，講稿共26頁，2023年5月2日，星期三3.其他多氯有機物電化學選擇性氫化脫氯3.1.三氯甲基苯Fig.3.1CVof5.0mMbenzenyltrichlorideandbenzylchloride,inCH3CN+0.1mMTBAPonAgelectrode(?2mm),at298K,v=100mVs-1,T=20℃.物理化學學報,2013,29:973.ZhejiangUniversityofTechnologyAgelectrodeAgelectrode15第15頁，講稿共26頁，2023年5月2日，星期三EntryEappa(V)Finalproductdistribution1-1.317%(5),48%(4E),35%(4Z)2-1.862%(10),21%(11E),17%(11Z)3b-1.292%(10),8%(toluene)Table3.1ElectroreductionofbenzenyltrichlorideatAgmesh(2.5×3.0cm2),in40mLcatholyte(CH3CN+0.1mMTBAP+5.0mMbenzenyltrichloride),at20℃.aAppliedpotentialvs.Ag/Ag+.bInpresentof1MCH3COOHZhejiangUniversityofTechnology16第16頁，講稿共26頁，2023年5月2日，星期三3.2.氯乙酸Fig.3.2CVsofthreeelectrodesinblank0.5MNaOH(1(blue),2,3(red))andinpresentof50mMTCAA(1(black,redandgreen))or50mMMCAA(2,3(black)),v=50mVs-1,T=298K.J.Electroan.Chem.,2012,664:39.ZhejiangUniversityofTechnologyCCl3COOH(TCAA)CH2ClCOOH(MCAA)Ag(p)Ag(r)17第17頁，講稿共26頁，2023年5月2日，星期三Fig.3.3CVsofAg(r)electrodeinblankaqueoussolutions+(1)0.05MTCAA,(2)0.05MDCAA,(3)0.05MMCAA,(4)nothing,at50mVs-1.ZhejiangUniversityofTechnology1---CCl3COOH(TCAA)2---CHCl2COOH(DCAA)3---CH2ClCOOH(MCAA)4---blankpH=2.2pH=718第18頁，講稿共26頁，2023年5月2日，星期三Fig.3.4ThereductionofTCAA(0.05M)usingAg(r)electrode,at298K,inaqueoussolutionsof(1)0.5MH2SO4,(2)0.5MNa2SO4and(3)0.5MNaOH.Fig.3.5Currentefficiencyforthereductionof0.05MTCAA,usingAg(r)electrode(2cm×3cm×0.1cm),usingappliedcurrent110mA,(1)0.5MH2SO4,(2)0.5MNa2SO4and(3)0.5MNaOH.ZhejiangUniversityofTechnology19第19頁，講稿共26頁，2023年5月2日，星期三

Fig.3.6SEM:(1)Ag(p)electrode,(2)Pd/Ag(p)electrode,(3)Ag(r)electrode,and(4)Pd/Agelectrode.3.3.

2,4-二氯苯氧乙酸Electrochem.Commun.,2009,11:2133;Electrochim.Acta,2013,96:90.ZhejiangUniversityofTechnologyAg(p)electrodeAg(r)electrodePd/Ag(p)electrodePd/Ag(r)electrode20第20頁，講稿共26頁，2023年5月2日，星期三Fig.3.7CVsoffiveelectrodesinblank0.5MNaOH(a,b,c,d(black),f(black))andinpresenceof25mM2,4-D(d(red,green),e,f(red)),ν=50mVs-1.ZhejiangUniversityofTechnology21第21頁，講稿共26頁，2023年5月2日，星期三EntryCathodesFinalproductdistributionCurrentEfficiency(%)Current(mA)/time(h)1Pd/GC1.7%PAA,98.3%2,4-D1.650/22Pd/Ag(p)9.9%PAA,49.6%ClPAA,40.5%2,4-D37.250/23Pd/Ag(r)-PdCl217.7%PAA,37.3%ClPAA,45.0%2,4-D77.925/24Pd/Ag(r)-PdCl237.4%PAA,49.1%ClPAA,13.5%2,4-D66.450/25Pd/Ag(r)-PdCl225.3%PAA,37.2%ClPAA,35.5%2,4-D31.475/26Pd/Ti6.8%PAA,6.1%ClPAA,87.1%2,4-D21.125/27Pd/Ti5.7%PAA,5.5%ClPAA,88.8%2,4-D9.150/28Pd/Ti4.5%PAA,4.9%ClPAA,90.6%2,4-D5.075/29Pd/Ag(r)-PdSO410.1%PAA,46.5%ClPAA,43.4%2,4-D71.525/210Pd/Ag(r)-PdSO426.2%PAA,48.1%ClPAA,25.7%2,4-D53.950/211Pd/Ag(r)-PdSO412.4%PAA,32.3%ClPAA,55.3%2,4-D20.475/2Table3.2Electroreductionsof25mM2,4-Din0.5MNaOH,onfourdifferentelectrodes(3×4cm2).PAA:

phenoxyaceticacid;ClPAA:2-Cland4-Cl-phenoxyaceticacid;2,4-D:2,4-diCl-phenoxyacetica