Organocatalytic Enantioselective Tandem Michael Addition and Cyclization Reaction of Trisubstituted 2‐Nitro‐1,3‐enynes with Cyclic 1,3‐Diketones

An enantioselective tandem Michael addition/cyclization reaction between trisubstituted 2‐nitro‐1,3‐enynes and cyclic 1,3‐diketones catalyzed by a chiral organosquaramide catalyst in the presence of Ag 2 CO 3 was developed. The chiral functionalized chromene products could be obtained in good yield and in 80–99% enantiomeric excess. The structures and absolute configurations of some of the products were confirmed by X‐ray crystallographic analysis. magnified image