Synthesis Of Biaryl Derivatives And Pyran Derivatives Via One Pot Tandem Multicomponent Reactions

Multicomponent reaction is one type of reaction based on combinatorial chemistry and diversity oriented synthesis. Ugi considered the multicomponent reactions are three or more reactions processes consecutively to generate the target products in one flask, and the target molecule included all segments of the starting molecules. Usually, multicomponent tandem reaction consists of multiple pairs of molecules to react in a certain order. Not all of the reactants involved in reactions at the same time, and usually contains into irreversible step.Multicomponent reactions have become an efficient and powerful tool in modern synthetic organic chemistry attribute to their valued features, such as atom economy, easy purification of products, simplicity of operator, and the reactions can avoid the protection and deprotection of functional groups. Multicomponent reactions are widely applied in the synthesis of natural products and drug development.Palladium catalyzed Suzuki coupling reactions have emerged as some of the most importantC-C bond forming methodologies in modern synthetic chemistry. Coupling products are widely applied as intermediates in natural products, pesticides, dyestuffs, and polymers.Our group has been focused on the development of organic synthetic protocols. We interest in developing new multicomponent reactions and synthesis of some multi-functional groups molecules. In this thesis, we combined the Suzuki reaction with various multicomponent reactions sequently in one pot to construct a new kind of tandem multicomponet reaction. A series of novel structure of poly-functional heterocyclic compounds were sinthesised successfully. This thesis includes the following aspects:1. Using Pd/C as catalyst, we combined the Suzuki reaction with knoevenagel reaction sequentially in one pot to form a new tandem multicomponent reaction. A series of biaryl derivatives were synthesized by the mentioned method. This procedure offers several advantages including mild reaction condition, convenient procedure, and environmental friendliness.2. Using Pd/C as catalyst,4-bromobenzaldehyde, phenylboronic acid, activated methylene compounds, and carbonyl compounds were assembled consecutively in one pot to produce a new tandem multicomponent reaction. A series of novel structure of poly-functional pyran derivatives were prepared effectively. The products include20new compounds. This method offers merits of high yield, short time, and easy handing.