Copper-aluminium Hydrotalcite System Prepared By A Facile One-pot Method:A Highly Active And Recyclable Catalyst For The Synthesis Of Indole And Phenyl Ether

N-heterocycles,especially indole,are a type of important precursor for synthesizing chemicals,drugs,dyes and pestcides.Diaryl ether played important role in synthesizing a lot of substrates which contain biological activity,such as Vancomycin aglycone and Combretastatin.At the same time,it has wide use in fine chemical synthesis,polymer industry,agrochemicals and organic transformation reactions of metal catalysis.It is a challenging searching direction to develop a more efficient method of synthesizing indole and diaryl ether.This article used one-pot method to synthesize a new type of CuAl-HT.Three different catalysts were named CuAl-HT1,CuAl-HT2,CuAl-HT3 respectively.We conducted TEM,XRD,XPS and elemental analysis for this catalyst,and studied its activity of synthesizing indole and diaryl ether.The study indicated that conversion of 2 amino benzene ethanol reached 100%under the alkaline conditon of potassium tert-butoxide and we used orthoxylen as solvent at the temperature of 140?Cand after 12 hours.The catalyst was used for 6 consecutive trials without significant loss of its reactivity.Calcium chloride as Lewis acid has excellent promotion for the synthesis of indole.According to the experiment,we also developed possible reaction mechanism of intramolecular dehydrogenation to synthesize indole.The catalyst has excellent catalyzing activity for the synthesis of diary]ether by using the Ullmann-type coupling reaction of benzene and phenol iodine.We used potassium fluoride as alkaline and CuAl-HT3 as catalyst at the temperature of 135?in the DMSO solvent.The conversion percent of iodobenzene has reached 95%.The catalyst was used for 6 consecutive trials without significant loss of its reactivity.