Research On Para-Quinone Methides By Lewis Acids

Para-quinone methides(p-QMs)as an important intermediate in organic synthesis transformation,that are widely present in natural products,bioactive molecules and pharmaceutical molecules;in addition,it is important in the fields of dyes,pesticides and biopharmaceuticals.As we all know,p-QMs has electrophilic and it can produce1,6-conjugated addition products or cyclization.products with nucleophiles,such as triarylmethane or diarylmethylamine compounds.But such reactions are not perfect,for instance it has greater substrate restrictionused,or it used relatively expensive catalysts,and the economy of the overall reaction is not ideal,the most important that the most reactions can't achieve green synthesis.Inspired by the synthesis of the above two types of compounds,we developed a novel method that based on Lewis acid catalysis.the reaction conditions were mild,and we successfully get the diversified synthesis of the above two types compounds.(1)Base on Silver(I)-catalyzed novel ipso-[2+2]cycloaddition and retro-Friedel–Crafts reaction of ortho hydroxyphenyl-substituted para-quinone methides,we successfully get the diversified synthesis of the triarylmethanes(TRAMs)and derivatives that has played an important role in medicinal chemistry.(2)Under the catalysis of carbocations,we successfully achieved the 1,6-conjugated addition of ortho-hydroxyphenyl-substituted para-quinone methides and aminobenzotriazoles,and it successfully get a series of diarylmethylamine compounds with nitrogen-containing heterocyclic skeletons.The reaction is used the carbocation as a catalyst and acetonitrile as a solvent,besides the reaction conditions are mild,we can get a pure product by simple filtration,and the filtrate can be applied repeatedly without yield loss.That above process is environmentally friendly and cost-effective,which is in line with the concept of green synthesis and has the potential for large-scale production.