A kind of method that catalyzes the hydroamination reaction of cyclohexylacetylene to prepare enamine compounds

Abstract

The invention provides a method for preparing enamine compounds by catalyzing the hydroamination reaction of cyclohexylacetylene, which is characterized in that, under the catalysis of the catalyst, cyclohexylacetylene and secondary amine undergo hydroamination reaction in a solvent , to obtain enamine compounds; the molecular formula of the catalyst is [R 1 R 2 C(C 5 h 4 N) 2 ] Pd=NPh, wherein, R 1 and R 2 independently selected from H, CH 3 and Ph, the solvent is an aromatic hydrocarbon, the reaction temperature is 60-100°C, and the reaction time is 6-12h. The invention has mild reaction conditions, high catalytic efficiency, high atom economy, low cost, easy separation of products, no large amount of waste residue, and is suitable for industrial production.

Description

technical field [0001] The invention belongs to the technical field of catalytic chemistry, and in particular relates to a method for preparing enamine compounds by catalyzing cyclohexylacetylene hydroamination reaction with divalent palladium imine complexes containing pyridine ligands. Background technique [0002] Enamine compounds play an important role in many fields, such as being suitable for the synthesis of various nitrogen-containing heterocyclic derivatives as precursors; they also have special medicinal properties, and exist as key structural units in many natural products and drugs; In addition, enamines are widely used as intermediates in the preparation of chiral amines. The traditional methods of constructing enamine mainly include condensation reaction, addition reaction, heterocyclic cleavage and imine to prepare enamine, and some special synthetic methods such as Curtius rearrangement, amide α, β elimination reaction and ketoxime reduction Acylation, etc....

AI Technical Summary

Problems solved by technology

The traditional methods of constructing enamine mainly include condensation reaction, addition reaction, heterocyclic cleavage and imine to prepare enamine, and some special synthetic methods such as Curtius rearrangement, amide α, β elimination reaction and ketoxime reduction Acylation, etc.; these methods have obvious deficiencies: (1) higher requirements for reaction conditions, such as high temperature and pressure or extremely low temperature; (2) low tolerance to different functional groups of reaction materials; (3) amino reagents The types are limited; (4) High requirements on the reaction system, such as absolute anhydrous and oxygen-free, few types of catalysts and high dosage, special ligands, etc.; (5) Restrictions on raw materials, such as single type of raw materials, cumbersome and difficult preparation, etc.

These deficiencies greatly limit the development of enamine chemistry

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