Method for synthesizing di-ferrocene phosphine diimine structure connected with aliphatic series and benzene ring

Abstract

The invention relates to a method for synthesizing planar chiral diferrocene phosphine diimide, and this ligand contains diimine and has a planar chiral diferrocene structure. This compound is condensed of planar chiral ferroceneprimary amide and various dialdehyde compounds under the existence of shrinking agent. The dialdehyde compounds can be p-phthalaldehyde, o-phthalaldehyde, m-phthalaldehyde, phenyl dialdehyde, butyl dialdehyde, glutaric dialdehyde, etc. and the method has the advantages of simple synthesizing route, simple operation, easy purification, and high yield. The invention is applied to the catalytic reactions such as aromatic ketone unsymmetrical hydrogen transfer reaction and can achieve very high yield and enantiotropic selectivity.

Description

Background technique [0001] Ferrocene catalyst ligands have high catalytic activity and high enantioselectivity in many reactions. The usual ferrocene catalyst ligands are mostly single ferrocene derivatives. These compounds are easily Soluble in most organic solvents, it is difficult to extract and separate after the catalytic reaction, resulting in a large number of expensive chiral ligands that are difficult to recycle, which greatly hinders the application of ferrocene derivatives in industrial asymmetric catalysis. Chiral bis-ferrocene phosphinodiimine ligands are a very important class of ligands. This type of ligand not only has double coordination ability, but also reduces the polarity of the bis-ferrocene structure, which is beneficial to realize recycling by utilizing the difference in solubility. [0002] Dai Huicong and others studied and synthesized a planar chiral bisferrocene Schiff base imine structure (molecular formula is as follows), and applied the ligand t...

AI Technical Summary

Problems solved by technology

[0001] Ferrocene catalyst ligands have high catalytic activity and high enantioselectivity in many reactions. The usual ferrocene catalyst ligands are mostly single ferrocene derivatives. These compounds are easily Soluble in most organic solvents, it is difficult to extract and separate after the catalytic reaction, resulting in a large number of expensive chiral ligands that are difficult to recycle, which greatly hinders the application of ferrocene derivatives in industrial asymmetric catalysis

However, for asymmetric cyclopropanation reactions, the enantioselective effect of this ligand is not very ideal, and the best ee value is only 65%.

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