The organic ligand - metal complexes as chiral cat -

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The organic ligand - metal complexes as chiral catalysts in asymmetric synthesis

Phenanthroline ligand in the structure of acid into lipid ligand of such acids, tartaric acid class, the three pyridine carboxylic acid. ① The malonate exposure for the skeleton of the two-oxazoline ligand - metal complexes. Ca (II) complex 4 after phenylhydrazine reduction is cu (1) complexes for catalytic styrene with ethyl diazoacetate (Ⅱ) A) in the cyclopropanation reaction. Almost the same time,[link widoczny dla zalogowanych], Anderson to D or L-tartaric acid of vinegar for a synthesized a series of double-ah oxazoline ligands 5. 5Nishiyama skeleton reported double-pyridine dicarboxylic acid ligands for a shower exposure yl 1 - (Ⅱ) complexes styrene and other olefins in the asymmetric cyclopropanation reaction gives high enantioselectivity results. ③ biphenyl, binaphthyl and ferrocene class dual-core dual-J Yan oxazoline ligand - metal complexes. 1995, Cotey synthesized biphenyl complexes 7, (R, R, R) for a 7 intramolecular reaction of propane,[link widoczny dla zalogowanych], the first enantioselective synthesis of bioactive substances to Sirenia, ee value reached 99% . In December 20O4 organic ligand - metal complexes as chiral catalysts for the asymmetric synthesis 3ll-Bu7Aim synthesis of a dual-core dual-ferrocene oxazoline ligands May 8,[link widoczny dla zalogowanych], and CutYI'f the ring complexes in styrene reaction of propane in the enantioselectivity to 99%. R8 ④ polymer-supported chiral oxazoline ligands Shu - metal complexes. Immobilization of the catalyst in recent years has become a new hotspot, Mayoral and its partners will tkxx (1) Jm. j: ~ covalent bonding with polystyrene and other polymers are 9 and so on, or bonded with silica gel. In the model reaction enantioselectivity and very small molecule ligands. 94. Supercritical co2 media reaction of chiral catalysts in supercritical coz (hereinafter referred to as the advantages of sccoD highlighted in the gas reactants with high compatibility, and ease of recycling in the traditional transition metal catalyzed reactions of transition metal catalysts is difficult to recover, but The downside is that most of the transition metal catalysts insoluble in the sc0 Therefore, recent research focused on improving Sca solubility in terms of transition metal catalysts. mainly looking for a suitable solvent and to obtain their substance of two aspects of pro-c used as the solvent of substances and fluorinated alkyl alcohol-based, such as Xiao Jianliang in ScI to the a, an asymmetric hydrogenation of unsaturated carboxylic acid mixture added perfluoroalkyl alcohol, make Ru increase the solubility of the catalyst, ee value increased, the pro-c of the nature of the research is focused on Ligand Modified, pull and surfactant ion balance in three areas, the transition metal catalyst containing aromatic substituents. to fluorinated alkyl, Fluorinated ethers or modified polysiloxane based in scc% could increase the solubility of perfluorinated alkane is the most representative on behalf of the pro-c ligand. charged complexes are generally not soluble in s (: cOz ,[link widoczny dla zalogowanych], but by the role of counter ions can improve the solubility, studies show that cationic charge distribution of the higher centers of mass for the counter anions of cationic transition metal ion complexes increase in the solubility scc%. G fluorocarbon solvent nature and hydrocarbons similar studies have shown that the lower cohesive energy, such as fluorocarbon polymers and polysiloxanes soluble in G,[link widoczny dla zalogowanych], can be used as pro-c surfactant to improve the transition metal complex catalysts in the solubility of scc% . Conclusion: asymmetric synthesis in medicine, agriculture and spices synthesis has been applied in recent years, chiral catalysts are more widely available and applied, this paper, the organic ligand - metal complexes as chiral catalysts of the recent progress . but these catalysts are still expensive and difficult to recycle and other shortcomings. particularly for drug synthesis, many metal compounds are banned, so there is no metal involved in the development of chiral catalysts is currently another hot topic.

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