Enantioselective Synthesis Of Heterotriarylmethane Through 1,4-Addition Reaction Of 3-Substituted Indole And Azadiene Catalyzed By Chiral Phosphoric Acid

Triarylmethane and its derivatives have attracted much attention due to its unique structure and physical properties,as well as its application in organic functional materials and biologically active compounds.Some triarylmethanes have become promising anti-tuberculosis,antiviral activities and acetylcholinesterase inhibitors.C-2 substituted triarylmethane derivatives and heterotriylarylmethanes are highly promising antibacterial drugs,and have antigenic properties.Therefore,the construction of heterotriarylmethane cores,especially in a catalytically asymmetric manner,has become a target of attention in the synthesis community.The importance of indole and its derivatives in biologically active natural products and pharmacologically significant substances has been fully documented.In reaction with electrophiles,the reactive position of indole(C3)is the most reactive position in the C2 or N1 position of other indole.We report the C 2 functionalization of indole Due to the low C2 activity of indole,the synthesis of C-2 substituted derivatives is still underdeveloped.The development of effective methods to directly asymmetrically synthesize C-2 substituted indole derivatives remains an important goal.There are a few reports describing the catalytic asymmetric process of azadienes,mainly focusing on transition metal catalysis,N-heterocyclic carbene(NHC),chiral amines,bifunctional Bronsted bases and phosphines,bifunctional chiral phosphoric acid As a powerful chiral organic catalyst,it has been widely used to activate oxygen and nitrogen-containing substrates.However,there are relatively few studies on the asymmetric conversion of azadiene by chiral phosphoric acid.On the other hand,azadiene The asymmetric catalyzed [4 + n] cyclization reaction of alkenes has developed rapidly,but the catalyzed asymmetric 1,4-addition reaction of azadiene is relatively lagging behind.Here,we developed an enantioselective 1,4-addition reaction catalyzed by3-substituted indole,pyrrole and furan,and substituted azadiene with acryloyl phosphate.A variety of C2-substituted triarylmethane derivatives have been obtained with moderate to good yields(up to 98%)and generally excellent enantioselectivity(up to 99%ee).