Synthesis Of Multisubstituted Pyrroles And Studies Of AIEE In Pyrrolo[1,2-a]Pyrimidine Derivatives

Pyrrole compounds exist widely in nature.The porphyrin ring constructed by pyrrole exists in animals and plants.It is an indispensable component of life.Pyrroles are among the most important heterocycles in pharmaceuticals and agrochemicals,widely used in medicines,dyes,and also play an important role in the field of materials.Due to the substitution diversity of pyrrole compounds,how to easily and efficiently obtain pyrrole compounds has always been an important research field in organic chemistry,especially the direct construction of pyrrole skeletons with different substituents and free NH group however,is very challenging.This thesis includes two sections:(1)Selective construction of asymmetric tetrasubstituted pyrroles from α,β-unsaturated imines.(2)Studies of AIEE on Pyrrolo[1,2-a]pyrimidine Derivatives.(1)Selective construction of asymmetric tetrasubstituted pyrroles from α,β-unsaturated imines: This study successfully achieved the one-step conversion of α,β-unsaturated imines to tetrasubstituted pyrroles.A series of pyrroles were obtained with up to 99% yield and good functional group tolerance.Mechanistic studies have shown that the reaction is a kinetically determined cyano addition at room temperature first,cyano migration occurs at high temperature,and then the cyano group undergoes secondary addition,then aromatization to form a pyrrole skeleton.(2)Studies of AIEE on pyrrolo[1,2-a]pyrimidine derivatives: As a synthetic application of 2-aminopyrrole,a series of pyrrolo[1,2-a]pyrimidine compounds were designed and synthesized from NH pyrroles and 1,3-diketones in one step.The phenomenon of timedependent aggregation-induced fluorescence enhancement was found with pyrrolo[1,2-a]pyrimidine compounds.After analyzing the crystal structures of several pyrrolo[1,2-a]pyrimidine photoluminescent solids,it is speculated that the crystal packing mode may account for the aggregation-induced emission enhancement.