上海有機(jī)所合成講義第5講

上海有機(jī)所合成講義第5講第1頁/共51頁BTMSA:雙三甲硅基乙炔第2頁/共51頁§3－1－2與環(huán)氧化合物的烷基化反應(yīng)第3頁/共51頁第4頁/共51頁第二節(jié)偶聯(lián)反應(yīng)第5頁/共51頁cat:Pd(O),(PPh3)2PdCl2,(PhCN)2PdCl2,Pd(Ph3P)4,(MeCN)2PdCl2,(dppf)PdCl2，

Ni(acac)2,(i-PrO)4Ti,(PPh3)3Rh(CO)H

第6頁/共51頁第7頁/共51頁第8頁/共51頁第9頁/共51頁第三節(jié)加成反應(yīng)Activatedalkynes第10頁/共51頁第11頁/共51頁(Cycloaddition)第12頁/共51頁第13頁/共51頁第四節(jié)還原反應(yīng)Dinuclearrhodiumhydridecomplex(反式烯烴）還原至烯烴第14頁/共51頁Catalystsreducingthealkynestotransalkenes

dissolvingmetal第15頁/共51頁conjugatedenynesusuallyyieldmixturesoverLindlarcatalystMono-nuclearcomplexes---tocisalkene第16頁/共51頁[(arene)Cr(CO)3]:highlystereoandchemo-selectivehydrogenationofinternalalkynestoCis-alkenes第17頁/共51頁Thealkenesonceformednolongerbindtothecomplexandhydrogenationdoesnotproceedfurthertogivealkanesorevenisomerized第18頁/共51頁Reductionsbynoncatalyticchemicalmethods

diimide(偶氮）－－completelycisalkeneTetrahedronLett.

1961,347

dissolvingmetal------transalkeneNa/NH3(liq.)

J.Am.Chem.Soc.,1941,63,216Li/alkylamine

J.Am.Chem.Soc.,1955,77,3378Ca/alkyamine

J.Org.Chem.,1984,49,1662Na/HMPA

J.Org.Chem.,1974,39,747

J.Org.Chem.,1970,35,3565

Yb/NH3(liq)J.Org.Chem.1978,43,

4555

第19頁/共51頁ActivatedZinc－inthepresenceofaprotonedonor(alcohol)---cisalkeneLow-valentmetalspecies

CrSO4---transisomer,inaqueousDMF第20頁/共51頁Metalhydride-transitionmetalhalidecombinationsLiAlH4/TiCl3orNiCl2,J.Org.Chem.1978,43,2567

TetrahedronLett.1977,4481NaBH4/Co(II)onlyreducingthealkynetoalkene

J.Org.Chem.1979,44,1014MgH2/CuIgivecisisomer

J.Org.Chem.1978,43,757

存在過度還原的問題其它HydroborationHydroaluminationhydrosilylation第21頁/共51頁第五節(jié)其它反應(yīng)1）炔烴的異構(gòu)化KAPA：3－氨基丙基氨基鉀第22頁/共51頁2）過渡金屬催化的異構(gòu)化

第23頁/共51頁3）Kinugasa反應(yīng)第24頁/共51頁第25頁/共51頁第26頁/共51頁第四章醇的反應(yīng)第27頁/共51頁第一節(jié)氧化反應(yīng)綜述參見：ComprehensiveOrg.Syn.,Vol.7,pp251-327.Stoichiometries:第28頁/共51頁§4-1-1鉻氧化劑CollinsReagent:CollinsTetrahedronLett.1968,3363;Org.Syn.1972,52,5.-CrO3-pyr2,alkalineoxidant-Hygroscopic,redcrystallinecomplexCanalsobeisolatedandstored,butusuallygeneratedinsitubyCrO3+pyr(SarettReagent)J.Am.Chem.Soc.1953,75,422.

注意:將

CrO3

加到

pyr,notpyrtoCrO3(易燃)-適用于酸敏感底物

Radcliffe改進(jìn):現(xiàn)場制備并用CH2Cl2作溶劑,J.Org.Chem.1970,35,4000.無過度氧化第29頁/共51頁

丙酮作溶劑可防過度氧化對(duì)酸敏感的底物不適用2.JonesReagent:JonesJ.Chem.Soc.1953,2548;J.Chem.Soc.1946,39.-酸性條件下，H+可催化反應(yīng)-對(duì)伯醇有可能會(huì)發(fā)生深度氧化成酯:在稀濃度條件下可阻止酯化反應(yīng)發(fā)生第30頁/共51頁

Brownoxidation:

runundertwophasereactionconditions,Et2O-H2O,J.Org.Chem.1971,36,387.[R4N]2Cr2O7

Synth.Commun.1980,75.Oxidationofallylic/benzylicalcoholsunderneutralconditions.3.PyridiniumChlorochromate(PCC):CoreyandSuggsTetrahedronLett.1975,2647.Usuallyonlyneed1-2equivofCr(VI)reagent(Jones&Collinsusuallyrequire6equiv)-PCCslightlyacidicwhichcancausesidereactions,forexample:第31頁/共51頁-ToavoidH+catalyzedsidereaction,usesodiumacetatebuffer:CantakeadvantageofacidityinPCCreaction(BogerandCoreyTetrahedronLett.1978,2461):第32頁/共51頁[3,3]-sigmatropicrearrangement,DaubenJ.Org.Chem.1977,42,682.第33頁/共51頁4.PyridiniumDichromate(PDC):CoreyTetrahedronLett.1979,399.Note:Crbasedreagentswilloxidizeaminesandsulfides.Substrateswiththesefunctionalgroupsmustbeoxidizedwithotherreagents(PDCwillsometimesleavesulfidesunaffected).5.CrO3-H5IO6:ZhaoandReiderTetrahedronLett.1998,39,5323.-CatalyticinCrO3(1-2%,Industrialscalechromium-basedoxidations)noracemization第34頁/共51頁§4-1-2錳氧化劑1.ManganeseDioxide(MnO2)第35頁/共51頁2.KMnO43.R4NMnO4-SamecapabilitiesasKMnO4butsolubleinorganicsolvents4.Cu(MnO4)-6H2OandBaMnO4BaMnO4-Al2O3-CuSO4第36頁/共51頁P(yáng)ossibleMechanismfortheOxidationofUnsaturatedAlcohols(CuMnO4-Al2O3)IIIPossibleMechanismfortheOxidationofSaturatedAlcohols第37頁/共51頁§4-1-3其它氧化劑1.RCH2OHorR2CHOHoxidation2.m-CPBAandNaIO4(Amineandsulfideoxidation)3.TPAP,[Pr4NRuO4]第38頁/共51頁4.Dess-MartinOxidation:DessandMartinJ.Am.Chem.Soc.1978,100,300;J.Am.Chem.Soc.1979,101,5294;

J.Org.Chem.1983,48,4155;J.Am.Chem.Soc.1991,113,7277.第39頁/共51頁5.Nitroxide:ToriiJ.Org.Chem.1990,55,462;SkarzewskiTetrahedronLett.1990,31,2177.6.TritylCation:JungJ.Am.Chem.Soc.1976,98,7882.7.Pt-O2:FuchsandHutchinsonJ.Am.Chem.Soc.1987,109,4755.-Goodforoxidationof1°alcoholsdirectlytocarboxylic