Studies On Synthesis, Characterization, Catalytic Properties Of Metal Complexes Supported By Chiral Tridentate Anilido-Imine Ligands

Nitrogen-containing organic compounds, which is chemical intermediates, finechemicals, pharmaceutical intermediates of commercial importantly, plays an importantrole in the field of medicine, scientific research and chemical industry. Amine, anitrogen-containing organic compounds, have a wide range of industrial applicationssuch as solvents, additives, drugs, fungicides, flotation aids, anti-foam agents, corrosioninhibitors, detergents and dyes. Hydroamination, belonging to efficiently atomiceconomic reaction, is an effective way to synthesize amine, which directly attack theunsaturated carbon-carbon bond by an amine through a electrophilic addition reactionand produce a higher level an amine or imine. Because of some special factors, it leadto occur the reaction only changing reaction pathways through catalysis. At present, thescientific community is committed to research intramolecular asymmetrichydroamination. The study of synthesizing highly selective and active chiral catalyst hasbecome a research hotspot in recent years. So far, the central metal types of chiral metalcomplexes catalyzing asymmetric hydroamination include alkali metals and alkalineearth metals, group4/5metals, last-transition metals, rare earth metals, actinides. Inrecent years, the report of rare earth elements catalyst efficient catalytizingintramolecular asymmetric hydroamination emerge in endlessly. Its high selectivity andhigh activity has been received the consensus of scientists. however, it hampers thefurther development of rare earth catalysts due to the rare earth elements much moreexpensive than metals, large toxicuty, high sensitivity, easy preparation and othershortcomings. Alkali metals and alkaline earth metals, with the advantages ofresource-rich, safety and nontoxicity, similar structure to rare earth elements andbiocompatibility has been concerned about by scientists. The same with group4/5metalbecause its low toxicity, low sensitivity and special catalytic activity with the rare earthelements. Because of the short development time of these type metals, the few reports ofefficient high selectivity and activity catalytic hydroamination, how to design andsynthesize a series of excellent and efficient ligand and alkali metal or alkaline earthmetal and group4/5metal complexes which catalytise intramolecular asymmetrichydroamination is an important issue. In this paper, we design and synthesize five chiral tridentate amine imide ligandsLA1H-LA5H, which are characterized by Elemental analysis,1H NMR and13C NMRspectrum. We afford four chiral tridentate amine imide complexes CB1-CB4through thereaction of this series ligands and [Mg(CH2Ph)2(THF)2]/ZrCl4(THF)2. All of thecomplexes were measured by Elemental analysis,1H NMR and13C NMR. Some ofthem are characterized by Crystal structure analysis. We also synthesized nine enaminesubstrate S1-S9for catalytizing hydroamination. Finally, we use these metalcomplexes by methods of in situ catalysis adding TMSCH2Li or directly catalysis tocatalytise intramolecular asymmetric hydroamination. The experiments showed that thecatalyst activity can be high at room temperature to the hydroamination. We observeimpact on different ligand substituent and different substrate to reactivity and selectivity.The experiment data study launched to the reaction mechanism. Reaction selectivity canreach a maximum ee value of65%, with moderate level. Wherein the alkaline earthmetal magnesium complexes cat(c) can reach up to45%selectivity, which is the secondhighest in the examples reported in the literature for the known alkaline earth metalcatalysis catalyzing intramolecular asymmetric hydroamination. It rank only second toSadow Task. however, there is a great distance from the high selectivity of the catalyst.