Synthesis And Properties Of 2H-Isoindoles And 1,3,4-Oxadiazoles

Isoindoles and their derivatives have applications in medicinal chemistry,namely as potential antitumor agents due to their antiproliferative activity,and in materials science,due to their high fluorescent and electroluminescent properties.They can also serve as useful synthetic building blocks in organic synthesis.Therefore synthetic methods are required to access differently substituted isoindoles from stable starting materials.1,3,4-oxadiazoles have a wide range of biological activities such as antimicrobial agents,anti-inflammatory agents,anticancer agents,muscle relaxants,and antimitotics.Due to myriad biological applications of 1,3,4-oxadiazole scaffolds,efficient and mild methods to synthesize these moieties have attracted considerable interest.In this thesis,a series of substituted isoindoles were synthesized by Palladium-catalyzed cyclization of phenylacetamides derived from Ugi-3-component reaction.Furthermore,we also prepared a series of 1,3,4-oxadiazoles through phosphine(III)/phosphine(V)oxide catalytic cycle.Details were summarized as follows:1.The development of Ugi reaction and applications of isoindoles and 1,3,4-oxadiazoles are introduced.2.A novel synthetic method of isoindoles via a tandem Ugi-3-component reaction and Palladium-catalyzed cyclization has been developed.Isonitrile,amine and aldehyde were used as raw materials to synthesize 2H-isoindole-1-carboxamides.Following are the synthetic routes.3.A series of 2-amino-1,3,4-oxadiazoles were obtained via the dehydration of semicarbazide with triphenylphosphine used in catalytic amount.Meanwhile,the inexpensive tetramethyldisiloxane(TMDS)were used as reductant.Following are the synthetic routes.