Environmentally Friendly Synthesis Of Benzyl Esters And Homoallylic Amines From Organozinc Reagents

Organozinc reagent is one of the earliest prepared organometallics. The application of organozinc reagent in organic synthesis has been limited for a long time because of their low reactivity. But just for their low reactivity, organozinc reagents have many advantages, such as generally compatibility of many functional groups, high chemoselectivity and stereoselectivity etc. The reaction of organozincs and carbonyl compounds are an important class of reaction for the formation of C-C bonds in organic synthesis.In recent years, the green chemistry is becoming an important research in modern chemistry. Looking for the environment-friendly reaction medium is one of an important topics of green chemistry. Polyethylene glycols (PEGs) have received increasing attention in recent years. It is a non-toxic, inexpensive, thermally stable, recoverable and biologically acceptable reagent, which represents a very attractive medium for organic reactions and have been wildly applied in biotechnology, medicine and organic synthesis.This thesis includes four chapters:Chapter one: The Development of Preparation and Application of Organozinc Reagents in Organic Synthesis.In this chapter, a brief introduction of the development on the organozinc reagents was given, and then reviewed in detail on the preparation and application of functional organozinc reagents in organic synthesis.Chaprer two: Three-component Synthesis of Benzyl Esters from Organozinc ReagentsThis chapter includes two parts. Part one: Catalyst-free One-pot, Three-component Synthesis of Benzyl Esters from Organozinc Reagents. We used aromatic aldehydes, acyl chlorides, benzylzinc bromide as substrates, and seventeen benzyl esters were synthesized under catalyst-free condition. The main advantageous of this method are easy operation, simple post treatment and high yield. Part two: Three-component Synthesis of Benzyl Esters from Organozinc Reagents in Polyethylene Glycol 400 (PEG-400). We investigated a one-pot three-component reaction for the conversion of aromatic aldehyde to the corresponding esters in the presence of benzylzinc bromide in polyethylene glycol 400. Compared with the method of three-component synthesis of benzyl esters from organozinc reagents under catalyst-free condition, the advantageous of this method are shorter reaction time and higher yield.Chaprer three: Efficient Method for the Synthesis of Homoallylic Amines Using Allylzinc Bromide in Polyethylene Glycol 400 (PEG-400).In this chapter, we studied the reaction of allylzinc bromide and aldimine in polyethylene glycol 400, and gained thirteen homoallylic amines. Advantages of the present method are easy operation, short reaction time and high yields.