Pd-catalyzed enantioselective [4 + 4] dipolar cycloaddition of aliphatic 1,4-dipoles with azadienes to access eight-membered N-heterocycles

A novel asymmetric [4 + 4] dipolar cycloaddition of aliphatic 1,4-dipoles with azadienes was developed to construct chiral benzofuran- and indene-fused eight-membered N-heterocycles in good yields and excellent stereoselectivities.