稀土金属有机化学PPT课件

1、LnLnClClLn一.一. Typical Lanthanide Complexes and Synthetic MethodologiesLnSSNa or KCpNa + LnI2第1页/共98页MM = Na, or K,2+ LnI2LnII(THF)nTHF(C10H8)YbI(DME)22+ 2YbIOOOO2第2页/共98页LnCl(THF)Orac / mesoNaDMEOLnIIOO mesoO1) K, THF/r. t.2) LnI23) DME第3页/共98页D2+ (Me3Si)2N3Ln(-Cl)Li(THF)3nTolueneDnDnLnIIn = 1, D =

2、OOONn = 2, D = Me2N-; MeO-;Nn = 3, D = Me2N-Ln = Yb, EuRHRRR = H, or Me, or Me3Si, or tBuNHSiMe2NSiMeMe第4页/共98页LnClClLnLnHHLnNaHLnRRLnLiCH2SiMe3H2LiNR1R2LnNNLnR1R2R1R2第5页/共98页LnCl(THF)n+ LiCH(SiMe3)2LnCH(SiMe3)2H2LnHHLn第6页/共98页SiLnN(SiHMe2)2+ 3 AlHiBu2hexane, r. t.SiLnSiHHLnLn = Y, 4 days, 72%Ln = H

3、o, 10 days, 46%第7页/共98页SiLnN(SiHMe2)2Si+ LnN(SiHMe2)23(THF)2第8页/共98页SiLnN(SiHMe2)2+ 2 AlR13, r. t.hexane-R2AlN(SiHMe2)2SiLnR1R1AlR1R1+ THF+ 2 AlR13- AlR13(THF)SiLnR1THF第9页/共98页Lanthanide CarbeneJ. Am. Chem. Soc., 2007, 129 (17), 5360 -5361. 第10页/共98页Organometallics, 2007, 26 (13), 3167 -3172, 第11页/共

4、98页Organometallics, 2008, ASAP Article, 第12页/共98页Lanthanide Phosphinidene ComplexJ. Am. Chem. Soc. 2008, 130, 2408-2409第13页/共98页LnI2(THF)xLn = Yb, Eu, SmLnI2(THF)x and related complexesLn = Tm, Dy, Nd第14页/共98页(C9H7)2Sm(THF)x + N2OTHF, 15 min(C9H7)2Sm(THF)2(-O) +(C9H7)3Sm(THF)二. ReactivityStoichiomet

5、ric Reactions(C9H7)2Sm(THF)x + C8H8THF, 15 min (C9H7)Sm(C8H8)(THF)x+ (C9H7)3Sm(THF)2, 2-bipyridine(C9H7)Sm(C8H8)(biPy)第15页/共98页(C9H7)2YbII(THF)2 +HCNCHNtButBu(C9H7)2YbIIICHNCHNtButButolueneTHFYbIITHFTHF+HCNCHNButtButolueneYbIIICHNCHNtButBuTHF第16页/共98页(C9H7)2YbII(THF)2 +HCNCHN(C9H7)2YbIIICHNCHNtoluen

6、eTHF(C9H7)2YbII(THF)2 +MeCNCMeNtolueneNMePhNMePhPhYbYbNPhYbNYb第17页/共98页2 (C9H7)2YbII(THF)2 +MeCNCMeNtoluene-2 THFMeMeYbPhNPhNYb+ C9H8(C9H7)2YbII(THF)2 +HCNNtolueneCHNNHNNYb第18页/共98页第19页/共98页Si+ SmI2THFSi(8-46)C2B10H11NaSmIII= CTHFTHFSiCCLiLiGLiClLi(THF)4G = NMe2,OMe+ SmI2(8-58)SmSiSmClGGSi第20页/共98页C

7、atalytic Reactions1. Catalytic Hydrogenation5% Cp*2YMe(THF)1 atm H2, benzene rt, 1h, 72%H0.7%Me2Si(Cp)(C5H3R*)SmCH(TMS)21 atm. H2, heptane, rt, 1 h, 95%, 71% eeR* =Cp = C5Me4,第21页/共98页Cp*2LnRH2-RHCp*2LnHRRLnCp*2HH2RHH第22页/共98页RHHCp*2LnR + H2Cp*2LnCp*2LnH + RH(1)第23页/共98页Cp*2LnRH2-RHCp*2LnHHRnHRnLnCp

8、*2HRnLnCp*2-Cp*2LnH 脱氢H2HRnCH3HRn氢化环化的催化循环第24页/共98页2. Lanthanide Complexes Catalyzed Hydroamination/ Cyclization ReactionsH2NHNCat.Cat.SiNN(SiMe3)2Ln = Sm, NdLnMarks, T. J. et al, Organometallics 1999, 18, 2568第25页/共98页n-C5H11HNH2Nn-C5H11HHCH3HCat.SiNN(SiMe3)2SmCat. =Marks, T. J. ; et al, J. Am. Che

9、m. Soc. 1999, 121, 3633.第26页/共98页NH2Rcat. LY-N(TMS)2NnRL =NNEtEtEtEtNNPriPriorn = 1, 2Livinghouse, T. et al, Adv. Synth. Catal. 2006, 348, 701-704.Lanthanide Complexes Catalyzed Hydroamination/Cyclization Reactions of aminoalkynes第27页/共98页Cp*2LnEE = H, CH(TMS)2, N(TMS)2H2NnHECp*2LnNHCp*2LnNHCp*2LnNH

10、*H2NnNH*Catalytic Cycle for Hydroamination第28页/共98页3. Lanthanide Complexes Catalyzed Hydrophosphination/Cyclization ReactionsH2PHPCat.Cat.SiNN(SiMe3)2PhSmPhOr (Me3Si)2N3Lnnnn = 1, 2Marks, T. J. et al, J. Am. Chem. Soc. 2000, 122, 1824.Marks, T. J. et al, Organometallics 2003, 22, 4630第29页/共98页Cp*2Ln

11、CH(TMS)2E =CH(TMS)2Cp*2LnPHCp*2LnPHCp*2LnPH*H2PnPH*H2Pn+CH2(TMS)2第30页/共98页4. Catalytic Hydrosilylationn-C8H17n-C8H17PhH2Sin-C8H17SiH2Ph5% catalystPhSiH3, rt, 1-24h, 75%, 28:1+催化剂产率（%，分离）选择性Cp*2LuMeTHF98100:0Cp*2YbCH(TMS)291100:0Cp*2YMeTHF84100:0Cp*2SmCH(TMS)29011:1Cp*2NdCH(TMS)2853.2:1Cp*2LaCH(TMS)2

12、901.9:1Me2SiCp”2YCH(TMS)28431:1Me2SiCp”2SmCH(TMS)2981:2Me2SiCp”2NdCH(TMS)2891:2第31页/共98页3% Cp*2YCH(TMS)2PhSiH3, benzene, rt 92 h, 91%SiH2Ph3% Cp*2YCH(TMS)2PhSiH3,toluene, rt 18 h, 97%SiH2Ph3% Cp*2YCH(TMS)2PhSiH3, benzene, rt 96 h, 61%, 2:1dsSiH2Ph第32页/共98页n-C6H135% (C5Me4i-Pr)2YCH(TMS)2 PhSiH3, 50 0

13、C 12 h, 78%, 4:1PhH2SiHHSiH2Ph+n-C6H13n-C6H13OOn-C5H11 PhSiH3, 50 0C 24 h, 85%Cp*2YMe(THF)HSiH2Phn-C5H11OO第33页/共98页LaN(TMS)233 mol% cat.PhSiH3600C, 9hSiH2PhLivinghouse, T. ; et al, Organometallics 2004, 23, 12-14.第34页/共98页Cp*2LnRR3SiH-RSiR3Cp*2LnHRRLnCp*2HRHSiR3R3SiHCatalytic Cycle for Hydrosilylati

14、on reaction第35页/共98页Cp*2LnCH(TMS)2OBOHOBOCH(TMS)2Cp*2LnHRCp*2LnROBOHOBORH5. Catalytic Hydroboration Reaction第36页/共98页6. Guanylation of Aromatic AminesNHNHNRRRBuilding Block exists in many bioactive compoundsArNH2+CRNNRCat.NHNHNArRR?第37页/共98页ArNH2+CRNNRCat. (1 mol%)80 C, benzeneNHNHNArRRSiNLnRCH2SiMe

15、3(thf)nCat. =Zhang, W.; Nishiura, M.; Hou, Z. Chem. Eur. J. 2007, 13, 4037.第38页/共98页+ (Me3Si)2N3Ln( -Cl)Li(THF)3LnNMe3SiSiMe3Ln = Y(1), Sm(2), Yb(3)toluenereflux第39页/共98页RNC NRR1R2NHNHNNR1R2RR2 mol% Cat. toluene, r. t. or 110 CNHNHNR1RRR2 = H1,3 - H shiftCatalyst = 5-(CH2)2(C9H6)2LnN(SiMe3)2 ( Ln =

16、Y(1); Sm(2); Yb(3) )第40页/共98页entryCat.RAmineTp ( C) / time (h)ProductYield (%)a12Prir.t. / 1249322Cyr.t. / 12595 (95)b (92)c32Prir.t. / 1269342Cyr.t. / 1279552Prir.t. / 1289262Cyr.t. / 1299472Prir.t. / 12109582Cyr.t. / 12119692Prir.t. / 121296 (92)c102Cyr.t. / 121395112Prir.t. / 121492122Cyr.t. / 12

17、1591H2NH2NH2NNH2H2NOCH3H2NOCH3H3COCatalytic Addition of the Amine to the Carbodiimides第41页/共98页132Prir.t. / 121693142Cyr.t. / 121792152Prir.t. / 121892 (88)c162Cyr.t. / 121993 (95)b172Cy110 / 362080 (82)b182Pri110 / 3620No reaction a,b,c192Cy110 / 3620No reaction a,b,c202Pri110 / 122395212Cy110 / 12

18、2497222Pri110 / 242581 (84)b232Cy110 / 242685NH2NH2H2NClH2NBrH2NNO2H2NNO2H2NO2NCatalytic Addition of the Amines to the Carbodiimides第42页/共98页Catalytic Activity of the Cp-Free Lanthanide Amides on the Addition of Amines to CarbodiimidesR3NH2NCNR1R1cat.HNR2R2cat.?(Me3Si)2N3Ln( -Cl)Li(THF)3第43页/共98页H2N

19、NHCyNHCy+Cy = cyclohexylcat.CyNC NCyNsolventCat. = (Me3Si)2N3Yb( -Cl)Li(THF)3entry Cat. Loading (mol %) solvent temp. ( C) time (h) Yieldb (%) 15THFr.t.249223THFr.t.249531THFr.t.249540.5THFr.t.246650THF0 or 6024061toluener.t.249771Et2Or.t.249681hexaner.t.249691CH2Cl2r.t.2499第44页/共98页H2NNHCyNHCy+Cy =

20、 cyclohexylcat.CyNC NCyNsolventCat. = (Me3Si)2N3Ln( -Cl)Li(THF)31%entry catalyst ArNH2 yield 1Ln =YbPhNH2962Ln = YPhNH2973Ln = EuPhNH2964Ln = SmPhNH2985Ln = LaPhNH2996(Me3Si)2N3Yb PhNH2967(Me3Si)2N3Yb 4-O2NPhNH2938(Me3Si)2N3Y4-O2NPhNH292第45页/共98页050100150200250020406080100Yield(%)Time(min) (Me3Si)2N

21、3La( -Cl)Li(THF)3 (Me3Si)2N3Y( -Cl)Li(THF)3 (Me3Si)2N3Yb( -Cl)Li(THF)3 (Me3Si)2N3YbPlot of Yields of Guanidine versus Reaction Time. The Reaction was performed by treating 1 equiv. of aniline with 1 equiv. of N, N-dicyclohexylcarbodiimide. 第46页/共98页NR1+HNHNNArR1R11 mol % cat.solvent, 40 C, or 60 CCR

22、1NR1NCR1HNNR2R3R2 = H,R3 = ArHNR2R31, 3-H shiftentryR1R2R3NHproductyield1i-Pr4-Cl-phenylNH21932Cy4-Cl-phenylNH22983t-Bu4-Cl-phenylNH23954i-Pr4-Br-phenylNH2489(88)5Cy4-Br-phenylNH2593(98)6i-Pr2-O2N-PhenylNH2662(85)7Cy2-O2N-PhenylNH2776(90)8i-Pr4-O2N-PhenylNH28909Cy4-O2N-PhenylNH2994第47页/共98页RNC NRArN

23、HNRRArH2 mol % Cat. THF, 80 CCatalytic Addition of the C-H Bond to the Carbodiimide第48页/共98页entryCata.RArTp (oC) /time (h)ProductYield (%)a11PriPh80 / 3359222PriPh80 / 3359033PriPh80 / 3359041CyPh80 / 3368952CyPh80 / 3368563CyPh80 / 3368671Pri4-MeOC6H480 / 3378581Cy4-MeOC6H480 / 3388393Cy4-MeOC6H480

24、 / 33881101Pri4-FC6H480 / 33994111Pri4-ClC6H480 / 34095121Cy4-ClC6H480 / 34193Catalytic Addition of the alkynes to the Carbodiimides第49页/共98页Ln-N(TMS)2R1R2NHLn-NR1R2HN(TMS)2NRCNRNNNR1R2RRLnR1R2NHNHNNR1R2RRNHNHNR1RRR2 = HAB1, 3 - shiftLn = EBILnZhou, S. ; Wang, S. * et al, Organometallics 2007, 26, 3

25、755.Li, Q.; Wang, S.* et al, J. Org. Chem. 2007, 72, 6763.Ln-C CArArC CHHN(TMS)2ArC CHArNHNRRNNC CArRRLnAB第50页/共98页7. Lanthanide Complexes Catalyzed Olefin PolymerizationLnROMeO1, 4 additioninitiationORMeOLnconjugateadditionpropagationLnOOOMeRMeOR = N(SiMe3)2Cat. = Me2Si(Me4C5)(C5H3R*)LnN(SiMe3)2 O(

26、CH2H2C9H6)2LnN(SiMe3)2Qian, C. T.; et al, Organometallics 2001, 20, 3106.Yamamoto, Y.; Marks, T. J. et al, J. Am. Chem. Soc. 1995, 117, 3276.Anwander, R.; et al, Organometallics 2003, 22, 1212.第51页/共98页第52页/共98页第53页/共98页8. Lanthanide Complexes Initiated Cannizzaro Type DisproportionationCOHCONH2+YCl

27、3LiN(SiMe3)2+CH2OH(5 mol %)2NObioactive importance第54页/共98页The methodology for the preparation of amide from aldehydeRCOHRCONH2RCOOHwet-Al2O3, MeSO2Cl 100oCH2NOH.HClRCOHRCONH2COH+NHORh+NoOBeckmann RearrangementIndirect methodCatalytic reaction第55页/共98页Optimization of the reaction conditionsratioaT (

28、 C)solventCat. ()T (d)Yield of 3g(%)b1:1r. ttoluene52402:1r. t.toluene52853:1r. t.toluene52852:1r. t.C6H652852:1r. t.Et2O52652:1r. t.THF52402:1r. t.CH2Cl25202:1r. t.hexane52322:1r. t.toluene02472:1r. t.toluene22782:1r. t.toluene102802:10toluene52482:170toluene52402:1r. t.toluene51752:1r. t.toluene53

29、88CO2NONH2CH2OHO2N+3g4gCO2NOH2+ LiN(SiMe3)2YCl32- 10 %第56页/共98页Ar CHO2CAr2. H2O+ArCH2OHLiN(SiMe3)21. YCl3 (5 mol %)+134ONH2Reaction conditions: toluene as solvent; room temperature; 2-3d 第57页/共98页Ar-T (d)Product of 3Yield of 3 (%)bProduct of 4Yield of 4 (%)bC6H5-33a56(18)c4a62(21)c4-CH3C6H4-33b624b6

30、54-CH3OC6H4-33c584c604-ClC6H4-23e764e784-BrC6H4-23f824f784-O2NC6H4-23g854g854-F3CC6H4-23j834j814-Me2NC6H4-33k524k50The results of the reaction of aldehydes with lithium amide catalyzed by YCl3aReaction conditions: toluene as solvent; room temperature; bIsolated yield based on the lithium amide; cIso

31、lated yields in the absence of YCl3 are shown in parentheses.第58页/共98页LiN(SiMe3)2+CHOO2NCO2NONH2+CH2OHO2N22. H2O1. LnCl3 (5 mol %)3g4gThe effects of lanthanide metal on the reactionLnnoneYPrNdSmEuDyHoYbYield of 3 (%)478560827870758085第59页/共98页The mechanism of the catalytic reactionLiN(SiMe3)2CHOO2N+

32、CO2NONH22 YCl3+CH2OHO2N 5 mol %85%85%CHOO2N+CO2NONH2LiN(SiMe3)22+CH2OHO2N47%49%YN(SiMe3)23CHOO2N+CO2NONH26+CH2OHO2N82%79%33CHOO2N+CO2NONH26(Me3Si)2N3Y( -Cl)Li(THF)3+CH2OHO2N88%80%33LnCl3 + 3LiN(SiMe3)2(Me3Si)2N3Ln第60页/共98页62. H2O+3a-m4a-m1.1equiv.of(Me3Si)2N3Y( -Cl)Li(THF)3OHRONH2RCH2OHR33第61页/共98页A

33、r-solventTime (d)Product of 3Yield of 3(%)bProduct of 4Yield of 4 (%)b4-O2NC6H4-CH2Cl223g934g884-O2NC6H4-C6H623g884g804-O2NC6H4-toluene23g884g804-O2NC6H4-Et2O23g704g724-O2NC6H4-THF23g474g50C6H5-CH2Cl233a584a624-CH3C6H4-CH2Cl233b684b704-CH3OC6H4-CH2Cl233c584c552-CH3OC6H4-CH2Cl233d574d594-ClC6H4-CH2Cl

34、223e784e764-BrC6H4-CH2Cl223f824f782-Furyl-CH2Cl223h774h70C6H5CH=CH-CH2Cl233i524i584-F3CC6H4-CH2Cl223j904j854-Me2NC6H4-CH2Cl233k564k502,4-Cl2C6H3-CH2Cl223l914l802,4-(MeO)2C6H3-CH2Cl33m654m60The results of reaction of aldehydes with yttrium amide (Me3Si)2N3Y( -Cl)Li(THF)3第62页/共98页The results of the re

35、action probed by GC-MSOCHOCH2Cl2(Me3Si)2N3Y( -Cl)Li(THF)3+6H2OOCONHSiMe3+OCH2OSiMe333OCONH2OCH2OH+3h4h33第63页/共98页第64页/共98页COD+(Me3Si)2N3Y( -Cl)Li(THF)3CH2Cl2CONHSiMe3CD2OSiMe3+H2OCONH2CD2OH+63333The process of the hydride transfer in the reaction第65页/共98页Ar COOCH2ArH2OAr CONH2+ Ar CH2OHArCHOAr CONHS

36、iMe3Ar CH2OSiMe3(Me3Si)2N3Ln( -Cl)Li(THF)3?+Tischchenko reaction(Me3Si)2N3Ln( -Cl)Li(THF)3COOCH2(Me3Si)2N3Y( -Cl)Li(THF)3no reactionCOOC2H5(Me3Si)2N3Y( -Cl)Li(THF)3no reaction第66页/共98页The proposed mechanism for the Cannizarro-type reactionZhang, L.; Wang, S. et al. J. Org. Chem. 2006, 71, 3149-3153.

37、3 LiN(SiMe3)2LnCl3LnN(SiMe3)23ArCHOArHOLnN(SiMe3)2AArCHOArOLnCArN(SiMe3)2OBHHArCH2OSiMe3ArNOLnSiMe3ArN(SiMe3)2OCDEFArNSiMe3OLiLiN(SiMe3)2ArCH2OHH2OArNH2OH2ONHSiMe3OArH2O第67页/共98页9. Catalytic Cyclotrimerization of Aromatic IsocyanatesLn = Yb, YX= O, SLnNPh2+ PhN=C=XLnXCNNPh2PhShen, Q.; et al, Organom

38、etallics 2002, 21, 2529.Shen, Q.; et al, Organometallics 1997, 16, 3711.第68页/共98页Can Lanthanide Amides Selectively Catalyze Cyclotrimerization of Aromatic Isocyanates ? ArN=C=ONNNOOOArArAr(1)?NNOOArArCatCat.NNOOArArn第69页/共98页SiNNRRRRR1R1LnN(SiMe3)2OR, R1 = different substituentsLn = rare earth metal

39、sIf the lanthanide amides have different Metal-Nitrogen bonds, Whats the selectivity?第70页/共98页Synthesis of the lanthanide amides of Incorporating a diamido ligand with a CH2SiMe2 linkNHSiNH+ (Me3Si)2N3Ln(-Cl)Li(THF)3tolueneNSiNLnN(SiMe3)2THFLn = Yb(2), Y(3), Dy(4), Sm(5), Nd(6)第71页/共98页Dy ComplexSm

40、complexYb complexY complex第72页/共98页NCOcatalystsolvent3NNNOOO?第73页/共98页Optimized conditions on the cyclotrimerization of phenyl isocyanateEntryCat. (mol %)asolventTemp() / time (h)Yield (%)b13(3%)toluener.t./129923(2%)toluener.t./128333(1%)toluener.t./126643(1%)toluene80/129953(2%)THFr.t./129963(1%)T

41、HFr.t./129273(1%)THF50/129983(3%)CH2Cl2r.t./127193(3%)CH2Cl240/1299103(2%)CH2Cl240/1274113(1%)CH2Cl240/1262第74页/共98页Table. The influence of different rare earth metal amides on the cyclotrimerization of phenyl isocyanateEntryCat.(mol%)a solventTemp( C)/time(h)Yield (%)b12 (1%)toluener.t./126222 (1%)

42、toluene80/129932 (1%)THFr.t./129943 (1%)toluener.t./126653 (1%)toluene80/129963 (1%)THFr.t./129274 (1%)toluener.t./126284 (1%)toluene80/129994 (1%)THFr.t./1299第75页/共98页EntryCat.(mol%)a solventTemp( C)/time(h)Yield (%)b105 (1%)toluener.t./1261115 (1%)toluene80/1299125 (1%)THFr.t./1299136 (1%)toluener

43、.t./1256146 (1%)toluene80/1299156 (1%)THFr.t./1299continued第76页/共98页Data for the Cyclotrimerization of Different IsocyanatesentryCatR-t ( C) / T (h)Yield(%) t ( C) /time(h)Yield (%)12Phenylr.t./129950/12/23Phenylr.t./129250/129932Benzylr.t./129950/12/43Benzylr.t./129950/12/524-Isopropylphenylr.t./12

44、9950/12/634-Isopropylphenylr.t./124650/12817a34-Isopropylphenylr.t./125480/1299Conditions, solvent: THF; a solvent: tolueneWu, Y.; Wang, S.; et al, Inorg. Chem. 2008, in press.第77页/共98页NHNHSi(Me3Si)2N3Ln( -Cl)Li(THF)3NNSi+tolueneLnN(SiMe3)2THFSynthesis of the lanthanide amides incorporating a diamid

45、o ligang with a Me2Si Bridge Ln = Yb(7), Y(8), Eu(9), Sm(11), Nd(11)第78页/共98页Yb ComplexSm complex Nd ComplexY Complex第79页/共98页Catalytic Activity of the Complexes on Cyclotrimerization of Phenyl IsocyanateEntryCat. (mol%)aSolventTemp (C )Time (h)Yield (%)b11%THFroom temp 129721%tolueneroom temp122731

46、%Et2Oroom temp124441%n-hexaneroom temp124052%CH2Cl2room temp122461%THF4069371%THF40129780.5%THF40129790.25%THF401298100.25%toluene401221110.25%n-hexane401229Catalyst:(Me2Si)(2,6-iPr2C6H3)N2SmN(SiMe3)2(THF) (9) 第80页/共98页Influence of different rare earth metal amides on the cyclotrimerization of pheny

47、l isocyanate EntryCatalystaYield (%)b1(Me2Si)(2,6-iPr2C6H3)N2YbN(SiMe3)2(THF)982(Me2Si)(2,6-iPr2C6H3)N2YN(SiMe3)2(THF)973(Me2Si)(2,6-iPr2C6H3)N2EuN(SiMe3)2(THF)964(Me2Si)(2,6-iPr2C6H3)N2SmN(SiMe3)2(THF)985(Me2Si)(2,6-iPr2C6H3)N2NdN(SiMe3)2(THF)926c(Me2Si)(C6H5)N2YbN(SiMe3)2(THF)95d7c(Me2Si)(C6H5)N2S

48、mN(SiMe3)2(THF)98da Catalyst loading: 0. 25 mol %; b Isolated yield by running the reaction in THF at 40 C for 12h. c catalyst loading: 1 mol %; d Isolated yield by running the reaction in THF at 60 C for 24h 第81页/共98页Data for the cyclotrimerization of different isocyanatesEntry CatalystR-T ( C) / t

49、 (h)Yield (%)18Benzyl40/12h9429Benzyl40/12h95310Benzyl40/12h98484-Isopropylphenyl40/12h98594-Isopropylphenyl40/12h986104-Isopropylphenyl40/12h97784-Nitrophenyl40/12h088Cyclohexyl40/12h9099Cyclohexyl40/12h491010Cyclohexyl40/12h47第82页/共98页Crystal Structures of cyclotrimerization products第83页/共98页Selec

50、tive Reaction of Different Metal-Nitrogen Bonds with GreaseSiNNLnN(SiMe3)2OC4H8(Me2SiO)3SiNNLnN(SiMe3)2SiOSiNNLn(Me3Si)2NSiOLn = Yb(12), Sm(13)selective insertion to this bondnot insertion to this bond第84页/共98页Ytterbium complexSamarium complex第85页/共98页SiNNRRRRR1R1LnN(SiMe3)2ONCO+SiNNRRRRR1R1LnN(SiMe3)2NCOSiNNRRRRR1R1LnN(SiMe3)2NCONCONNNLnNSiRRR1RR1RCOCONCOProposed Catalytic Cycle第86页/共98页Heterolysis of the Ln-N BondCan the Ln-N Bond be Homolytic Cleavage?(L)2LnIIINR2(L)2LnIII + -NR2(L)2LnI