PowerPoint PresentationSlide 2Slide 3Slide 4Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23Slide 24Slide 25Slide 26Slide 27Slide 28Slide 29Slide 30Slide 31Slide 3215.1OrganometallicOrganometallic CompoundsCompounds (R-M)(R-M)Organomagnesium & Organolithium compds 15.1Lithium Diorganocopper (Gilman) Reagents 15.2Not covered: Organopalladium reagents, Heck reaction, carbenes, carbenoids, & alkene metathesis.Synthesis, Concepts and the FinalHCCCCHHHHHHHHMEHCCCCHHHHHHHHEM+Chapter 1515.2Organometallic CompoundsR-Mg-X or R-MH3CC MgBrHH(-)(-)(+)Recall pKa of alkanes:BH B++CHHHH3CCHHH3CH3CCMgBrHH15.3Prep of Organometallic CompoundsGrignard (organomagnesium compound) H3CCH2Br+ MgoetherH3CCH2Mg-BrH3CCH2Br:MgetherH3CC Mg BrHH(-)(-)(+)free radical likeH3CCMgBrHHcovalent and ionic view15.4Prep of Organometallic CompoundsGrignard H3CCH2Br+ MgoetherH3CCH2Mg-BrAlkyllithiumH3CCH2CH2-Br + 2LioetherH3C CH2CH2-Li+ LiBrH3CCH2CHHLiOR15.6Reactions - protic compounds (acids)H3C- ++H3C HMgBrHOCCH3CH3HBrMg+ -OCCH3CH3H+++CCHHIMgCH2CH3+-CCHCH2CH3HMgIH3CCH3CH3CLi+H NHHH3CCH3CH3CH+NHH-+Li+15.7Prep of R-M (Nu:- +M)alkyl halide (sp3) + metal e.g. Grignard or organomagnesium reagentBut also: vinyl halide (sp2) + metalaryl halide (sp2) + metalMgXether Mgo(metal)X+15.8Nucleophilic ReactionsMgX1. etherO+2. H+/H2O (neut.)OHMgX1. etherO++O2. H+/H2O (neut.)OHAttacks less hindered side of epoxide15.9LiOHHDTHF H+/ H2O(neut.)+-+OHHHDPrimary site inverted, secondary unchanged.Reactions15.10Lithium Diorganocopper ReagentsPrep and use in Synthesis(CH3CH2)2CuLi'ether'+2 CH3CH2Li + CuILiIR2CuLiRLi + CuI+ LiI'ether'(similar Grignard reagent can be made)'ether'+2 CH3MgI + CuI(CH3)2CuMgIMgI215.11Use: Substitution rxn, replace halidesbut cuprates are better'ether'+IH2CRH3CH2CCR(CH3CH2)2CuLi- +HHGrignards and alkyllithiums can be nucleophiles…..H3C LiTHFOSOORH3C+-+H+/H2O(neut.)15.12Use: Substitution, replace leaving groupTMS = trimethylsilylBrOTMSLiCuOH2ether+H+/H2O(neut.)IRR'RR'CuMgBr+2'ether'H+/H2O(neut.)addeliminate*ICuLiether2+H+/H2O(neut.)addeliminate**not really SN2, ignore mechanism, 2nd semester15.13Organometallic Compoundsearlier = RMgX or RLiLiOHO1. ether+2. H+/H2O (neut)Better2. H+/H2O (neut)OCuMgXHO1. ether+2Nucleophile attacks less hindered side of epoxide15.14SYNTHESISSMtargetOCN?Propose how to convert starting material (sm) to a targetrules: Use any number of stepsFor each step show: - necessary reagents- necessary conditions - expected product or products15.15SYNTHESISOCNstarting materialtargetCompare functional groups and carbon skeletonNeed: 1 carbon (CN) and ketone + nitrile from olefin15.16SYNTHESISretroanalysisOC:NBr+OHBrBr2H2OxsOCNSMtargetNC-/DMFPCC15.17SYNTHESISretroanalysisBr2H2OxsPCCNC-/DMFOHCNOC:N+RCO3H1. DMSO2. H2OPCCOCNSMtargetOBrOHBr15.18synthesissynthesisOOOHHow?“thoughts”--- join---OHOXCH3X+15.19synthesissynthesisplanOOOHHow?synthesissynthesisOOOHHow?OHOXCH3X+NaHO-H+NapolaraproticXO-NH2or R:-H3C-IOHgSO4H2OOOexpectedbyproduct+OHreverse?15.20NHXNHH+SMtargetNBS hvBrDMFNHHNH+15.21OHOHBrOOHORCO3H PBr3Mg/THFH+/H2O15.22BrOOORcompare carbon skeletonfunctional groupsconvert 2-bromopropeneto 2-hexanone15.23OOORBrcompare carbon skeletonfunctional groupsOXX15.24NH21 eq.HBrONH21 eq.BrHgSO4/H2OO+15.25OHBr+BrONH21 eq.NH21 eq.HBrO+HgSO4/H2OOHOH15.26BrONH21 eq.NH21 eq.HBrO+HgSO4/H2OBr1 eq.BrBr+BrH2Pd/CHOH2O+PCCBrH++15.27BrBrNH2(xs)HBrBrHow?dibromidesource?15.28BrNH2(xs)HBrdibromidesource?BrBrBrOH1.BH32.H2O2 HO-PBr3BrBrBrBrNBShvH2Pd-CBrH2Pd-CBrO-tBuBr2others?15.29BrBr2H2Pd-CBrO-tBuBrBrBrBrH2Pd-CNBShvBrOH1.BH32.H2O2 HO-BrPBr3BrBrNH2(xs)Hdibromidesource?others?15.30BrNH2(xs)HBrOH1.BH32.H2O2 HO-Br Base(NaHCO3)OBrH3COHHH3COHHH3COH:Bracemic15.31BrONH21 eq.NH21 eq.HBrO+HgSO4/H2OBrBr+OOHOHH2Pd/CPCC15.32I’ve enjoyed teaching the class! I appreciate your hard work.chapters 1-11, 15-15.2 3 hour exam, models, pencilNO calculators or cell phonesGrades submitted (VIP), scores posted ASAP.Grade - determined by either: (1) accumulated total points (tests + final + recitation pts) or (2) final exam grade WHICHEVER IS HIGHER!Final 200 pts: ~130 cumulative,~70 new material5:30 pm PSC 002, (possibly
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