Efficient Synthesis of Macrocyclic Dilactam Crown Ethers by Fast Addition Method

摘要

A simple and convenient method for preparing macrocyclic dilactam crown ethers containing N_2O_5,N_3O_3,N_3O_4,N_3O_S and N_2O_(10) donor atoms with 18-32 membered rings was developed.These compounds were obtained in the macrocyclization step under vigorous stirring conditions as well as fast addition of reactants.This step does not require external cyciization factors such as high dilution approach,template effect or nitrogen protection and provides the expected dilactams in high yields,ranging from 65-95%.The course of the reaction is assumed to depend on the occurrence of self assembly phenomena which are stimulated by a logic concentration in a selected solvent and the yields are improved by application of high speed stirring and fast addition of reactants.