Synthesis, Characterization And Catalytic Capability Of Chiral Salen-Mn(Ⅲ) Complexes Based On Binol And Amino Acids

Schiff-base complexes have attracted explosive interest in recent years due to their wide application in the field of catalytic asymmetric synthesis. In particular, the Salen-Mn(III) catalytic system had emerged as a highly reactive and a highly enantioselective system for the asymmetric epoxidation of non-functionalized alkenes. In order to improve the catalytic application of Salen-Mn(III) system, many attempts have been made to investigate the influence factors in the asymmetric catalysis (e.g., the catalyst structure, reaction condition, recovery and reuse of catalyst, and so on). The paper is focused on the design and synthesis of Mn(III)-Binol-Salen complexes and the investigation of steric factors, reaction condition, cooperation of chiral center, and recovery and reuse of catalyst.The catalytic properties of these complexes on unfunctionalized alkene have been tested and employed in the asymmetric epoxidation. they provided some useful information for the development of catalytic asymmetric synthesis.This paper consists of five chapters1. It was given a brief rewiew of the research progress about the studies in the catalytic asymmetric epoxidation and the character of different asymmetric catalytic system. Further more, the aim and significance of this thesis have been outlined.2. Herein, four novel chiral C2-symmetric Binol-Salen ligands H2L1-4 derived from chiral Binol as well as the corresponding Manganese(III) complexes have been designed and further synthesized, the influence of the different ligands to the catalytic properties of complexes have been investigated. The positive experimental results have proved that those complexes effective catalysts for the asymmetric epoxidation of alkenes. especially the catalyst derived from H2L Four ligands were involved in this chapter:N, N'-Bis ((S)-1,1'-2-hydroxy-2'-isopropoxy-3-naphthylidene)-1,2-ethylenediamine (H2L1)N. N'-Bis ((S)-1,1'-2-hydroxy-2'-isopropoxy-3-naphthylidene)-1,2-propanediamine (H2L2)(1R,2R)-(-)-N,N'-Bis((S)-1,1'-2-hydroxy-2'-isopropoxy-3-naphthylidene)-1,2-cyclohexanediamine (H2L3)(1R,2R)-(-)-N,N'-Bis((S)-1,1'-2-hydroxy-2'-isopropoxy-3-naphthylidene)-1,2-diphenylethylenediamine (H2L4)3. Four novel chiral unsymmetrical Binol-Salen ligands H2L5-8 derived from chiral 3-Formyl-2-hydroxy-2'-methoxy-1,1'-binaphthyl and half-unit amine with different substituted groups as well as the corresponding Manganese(III) complexes have been designed and synthesized. In order to further researth the influence of catalytic properties, one C2-symmetric Binol-Salen ligand H2L9 and corresponding Manganese(III) complexes have also been synthesized. The catalytic properties of complexes have been investigated. Experimental results have proved that the five complexes effective catalysts for the asymmetric epoxidation of alkenes. Five ligands were involved in this chapter:(S)-3-((E)-((1R,2R)-2-((E)-2-hydroxybenzylideneamino)cyclohexylimino)methyl)-2'-methoxy-1,1'-binaphthyl-2-ol (H2L5)(S)-3-((E)-((1R,2R)-2-((E)-3-tert-butyl-2-hydroxybenzylideneamino)cyclohexylimino )methyl)-2'-methoxy-1,1'-binaphthyl-2-ol (H2L6)(S)-3-((E)-((1R,2R)-2-((E)-3,5-di-tert-butyl-2-hydroxybenzylideneamino)cyclohexyli mino)methyl)-2'-methoxy-1,1'-binaphthyl-2-ol (H2L7)(S)-3-((E)-(2-((E)-3,5-di-tert-butyl-2-hydroxybenzylideneamino)phenylimino)methyl)-2'-methoxy-1,1'-binaphthyl-2-ol(H2L8)(1R,2R)-(-)-N,N'-Bis((S)-1,1'-2-hydroxy-2'-methoxy-3-naphthylidene)-1,2-diphenylethylenediamine (H2L9)4. Particular interest has been focused on the recovery capability for reuse and water-solubility of Salen-Mn(â…¢) complexes in the asymmetric epoxidation. The oligomeric catalyst could be recovered and recycled for the asymmetric epoxidation of non-functionalized alkenes. Based on these facts, three novel chiral symmetrical Binol-Salen ligands H4L10-12 with many different chiral center as well as the corresponding Manganese(â…¢) complexes have been designed and synthesized. To further researth the water-solubility of catalyst, two C2-symmetric Salen ligand H4L13-14 with inherent phase-transfer capability and corresponding Manganese(III) complexes have also been synthesized. The catalytic properties of complexes have been investigated under different reaction condition. Experimental results have proved that those five catalysts can recovered and recycled for server times without losing activity and selectivity. The positive experimental results provided some useful information for the development of highly active catalyst with recovery capability.Five ligands were involved in this chapter:(S)-3,3'-bis((E)-((1R,2R)-2-((E)-3-tert-butyl-2-hydroxybenzylideneamino)-1,2-diphen ylethylimino)methyl)-1,1'-binaphthyl-2,2'-diol(H4L10)(S)-3,3'-bis((E)-((1R,2R)-2-((E)-3,5-di-tert-butyl-2-hydroxybenzylideneamino)-1,2-di phenylethylimino)methyl)-1,1'-binaphthyl-2,2'-diol(H4L11)(S)-3,3'-bis((E)-((1S,2S)-2-((E)-3.5-di-tert-butyl-2-hydroxybenzylideneamino)cyclohe xylimino)methyl)-1,1'-binaphthyl-2,2'-diol(H4L12)5,5-methylenedi-[(R,R)-{N-(3-tert-butylsalicylidine)-N'-(3'-tert-butyl-5'-(N,N-dibutylmethylene)salicyladhyde)}-1,2-diphenylethylenedi amine] 1(H4L13)5.5-methylenedi-[(R,R)-{N-(3-tert-butylsalicylidine)-N'-(3'-tert-butyl-5'-(N.N-dibuty lmethylene)salicyladhyde)}-1,2-cyclohexanediamine] 1(H4L14)5. Four novel chiral unsymmetrical Salen-like ligands H2L15-18 derived from amino acids and 3,5-Di-tert-butylsalicylaldehyde as well as the corresponding Manganese(â…¢) complexes have been designed and further synthesized, the influence of the different ligands to the catalytic properties of complexes have been investigated. The positive experimental results have proved that those complexes effective catalysts for the asymmetric epoxidation of alkenes.Four ligands were involved in this chapter: (E)-2-(3.5-di-tert-butyl-2-hydroxybenzylideneamino)-N-(2-hydroxyphenyl)acetamide (H2L15)(R.E)-2-(3,5-di-tert-butyl-2-hydroxybenzylideneamino)-N-(2-hydroxyphenyl)propana mide (H2L16)(R,E)-2-(3,5-di-tert-butyl-2-hydroxybenzylideneamino)-N-(2-hydroxyphenyl)-3-meth ylbutanamide (H2L17)(R,E)-2-(3,5-di-tert-butyl-2-hydroxybenzylideneamino)-N-(2-hydroxyphenyl)-3-phen ylpropanamide (H2L18)...