Reactivity Of Rare-earth Metal Amido Complexes With Pyrrolyl And N-methyl Pyrrolyl-functionalized Indolyl Ligands And Synthesis, Structure And Catalytic Activity Of Novel Rare-earth Metal Amido Complexes

This thesis focused on the reactivity of the rare-earth metal amido complexes withpyrrolyl and N-methyl pyrrolyl-functionalized indolyl compounds and the synthesis,the structure and the catalytic activities of novel rare-earth metal amido complexes.This thesis consists of three parts: reactivity of rare-earth metal amides towardspyrrolyl-functionalized indolyl imido compounds and N-methyl pyrrolyl-functionali-zed indolyl imido or amido ligands; the hydrophosphonylation of both aldehydes andketones catalyzed by these novel rare-earth metal amido complexes bridged by μ3–Oatom; the addition of alkyne to a nitrile catalyzed by these rare-earth metal complexesof imino-coordinate lithium bridged bis(indolyl) amides.1. Reactivity of pyrrolyl and N-methyl pyrrolyl-functionalized indolyl ligandstowards the rare-earth metal amido complexesReactions of3-(2-C4H3NHCH=NCH2CH2)C8H5NH(1) with [(Me3Si)2N]3REIII(-Cl)Li(THF)3produced a series of novel complexes with C2-symmetric consisted ofthree rare-earth metal ions bridged by a3-O atom and two dianion ligandscoordinated to rare-earth metals [(-5:1):1:1-3-(2-C4H3NCH=NCH2CH2)C8H5N]REIII(3-O)(2-Cl)2(THF)2[N(SiMe3)2](RE=Y(2a), Eu(2b), Dy(2c), Er(2d), Yb(2e))for the first time. The further experiments on capturing the excluded gas withBr2/CCl4solution followed by the examination by GC-HRMS clearly conformed thatthe3-O group resulted from the cleavage of a THF ring with the release of ethylene. Treatment of N-methyl pyrrolyl-functionalized indolyl ligands with[(Me3Si)2N]3REIII(μ-Cl)Li(THF)3produced the rare-earth complexes with onlyN-coordinated indolyl ligand, with the ligand containing either imino or amino groups.The N-methyl pyrrolyl group in the ligand is not involved in coordination. In addition,no oxo bridge was formed in these complexes. These results suggested that thestructure of ligand play a essential role in the reactions of the unprotectedpyrrolyl-functionalized indole and the rare-earth metal amides, from which a noveltrinuclear rare-earth metal complexes incorporating an5:1-indolyl ligand and a-Ogroup was formed. It seems that imino conjugated pyrrolyl group would lead to anunusual reactive of this reaction.Reactions of3-(2-(N-CH3)C4H3NCH=NCH2CH2)C8H5NH (3) with [(Me3Si)2N]3REIII(-Cl)Li(THF)3produced two different types of complexes, one consisted ofbis(indolyl) groups1:1-[1-3-(2-(N-CH3)C4H3NCH=NCH2CH2)C8H5N]Li[-2:1-3-(2-(NCH3)C4H3NCH=NCH2CH2)C8H5N])REIII[N(SiMe3)2]2(RE=Yb(4a),Dy(4b))，and the other consisted of one indolyl group [(Me3Si)2N]2REIII [1:-2-3-(2-(N-CH3)C4H3NCH=NCH2CH2)C8H5N])(μ-Cl)Li(THF)(RE=Er(4c), Y(4d)).All of these complexes are hetero-nuclear bimetallic complexes consisted of arare-earth metal ion and a lithium ion. This structure was stablized by lithium bridgecoordinated with imino group from two indolyl ligands or by chloride bridge bondingwith rare-earth metal ion and lithium ion. Treatment of3-(2-(N-CH3)-C4H3NCH2NHCH2CH2)C8H5NH with [(Me3Si)2N]3YbIII(μ-Cl)Li(THF)3producedTHF-coordinate-lithium bridged bis(indolyl) rare-earth metal amido complex1:1-[1:1-3-(2-(N-CH3)C4H3NCH2NCH2CH2)C8H5N]2Li[THF])Yb[N(SiMe3)2]2.Because the hydrogen of the amino group of the ligand is not donated, the aminogroup coordinated with lithium ion in an1mode just using the lone pair of electronnitrogen atom. While the indolyl group coordinated to rare-earth metal in an1modethrough the nitrogen atom.2. Catalytic activities of the rare-earth metal amido complexes with μ3–O group forhydrophosphonylation of both aldehydes and ketonesThe catalytic activities of these lanthanide amido complexes with3-O group for hydrophosphonylation of both aromatic and aliphatic aldehydes and ketones wereexplored. The results indicated that these complexes displayed a highly catalyticactivity for the C P bond formation under mild conditions as well as undersolvent-free condition with the employment of low catalyst loadings (0.1mol%foraldehydes and1mol%for ketones). Thus, it provides a potential way to prepareα-hydroxy phosphonates.3. Catalytic activities of the imino-coordinate-lithium bridged bis(indolyl)rare-earth metal amido complexes for the addition of alkyne towards nitrileThe catalytic activities of these lanthanide amido complexes for the addition ofterminal alkynes towards aromatic nitriles were explored. These results reveals thatthese complexes displayed a good catalytic activity as a single-compenent catalyst forthe addition reaction of terminal alkynes to aromatic nitriles in moderate to goodyields. The catalytic reaction is compatible with a wide range of terminal alkynes andaromatic nitriles under an environmentally benign condition. The steric effect ofaromatic alkynes and aromatic nitriles had a more powerful influence on this reactionthan the electronic properties of the substituent on the phenyl ring. These advantagesof these complexes imply the potential applications of other rare-earth metal amidesin this field.