Abstract:
The work undertaken through this thesis is part of the development of new synthetic methods leading to biologically interesting molecules, whose main objective was to carry out multicomponent reactions resulting in original molecules.
This thesis is divided into three main chapters: the first and the second were the
subject of the study of new synthetic routes to 1,4-dihydropyridine via Hantzsch reaction, and the synthesis of highly functionalized tetrahydropyridines respectively and using two new catalysts for these syntheses. However, the third chapter contains two parts: in the first part we realized the synthesis of a range of secondary amines which have served as the starting material for the second part, which deals with the preparation of a series of new derivatives 4-hydroxy-1,4-benzoxazine synthesized via the reaction Petasis.
In the first chapter, we have described the use of a novel catalyst in the multicomponent Hantzsch reaction. The t-BuOK which is a basic catalyst was used with a catalytic amount of 10 mol% and led to a series of 1,4-dihydropyridine and
polyhydroquinolines with good to excellent yields.
Like in the second chapter, we studied the synthesis of tetrahydropyridine but using a Lewis acid catalyst. It is a derivative of triflates: Bi (OTf) 3, which showed good catalytic activity envres this synthesis and leads to the production of desired molecules in good yields.
Finally, in the first part of the last chapter we have synthesized a series of secondary amines via reductive amination rection. However, in the second part of this chapter we have prepared a series of 2-hydroxy-1,4-benzoxazine in a Petasis type reaction, where the reaction is a cyclocondensation between the amino alcohol previously prepared in the first Part, boronic acid, and glyoxal. This reaction has allowed us to get nine new products with good to excellent yields, which were the subject of a paper.