Efficient Synthesis Of Polysubstituted Quinolones And Chromones

Heterocyclic compounds,as important intermediates of drugs and chemical raw materials,are closely related to our lives.As a special nitrogen-containing heterocyclic compound,4-quinolones are a very important class of synthetic antibacterial drugs.They are widely used in the synthesis of medicine and pesticides,and as intermediates,they are also applied in other aspects.Therefore,the synthesis of 4-quinolones has been emerging in recent decades.It is worth mentioning that among the numerous quinolones,3-aryl-4-quinolones have significant biological activity,but the functional group at C3 position of 4-quinolones is rarely reported.The traditional synthesis methods of 3-aryl-4-quinolones are mostly multistep,involving transition metal catalysis,and having some problems such as harsh reaction conditions,low reaction efficiency,and insufficient tolerance of functional groups.Therefore,it is remarkable to use cheap materials to develop more environmentally friendly and efficient synthesis methods.On the other hand,chromone derivatives are widely found in nature due to their special skeletal structure and diverse biological activities,and have attracted the attention of researchers.The physiological activity of these compounds is closely related to their substitutions at different positions,and the chromone substituted at C3 position is particularly significant.What is of real interest is that the chromone derivatives of heterocyclic substituents at C3 position tend to exhibit outstanding specific activity.Among many reports about synthesis of chromone derivatives,the synthesis method of 3-aryl-chromone occupies a small proportion,and synthesizing chromone derivatives of heterocyclic substituents at C3 position is more challenging,and the main reason is due to the strong coordination of heterocyclic substituent,and the reported methods involve transition metal catalysis.Therefore,it is difficult to obtain chromone derivatives of heterocyclic substituents at C3 position by one stepIn this paper,we have developed the synthesis of multi-substituted 4-quinolones and chromones with ynones,sulfonamides and N-oxides as substrates in one step under transition-metal free.The main studies are as follow(1)Base-Promoted Michael Addition/Smiles Rearrangement/N-Arylation Cascade:One-Step Synthesis of 1,2,3-Trisubstituted 4-Quinolones from Ynones and Sulfonamides(2)Tandem reaction to 3-(2-quinolyl)chromones from ynones and quinoline N-oxides under transition metal-and additive-free conditions...