Michael-Addition Reaction of Malononitrile with α,β-Unsaturated Cycloketones Catalyzed by KF／Al2O3

A series of KF/Al2O3 catalyzed Michael-addition reactions between malononitrile and α,β-unsaturated cycloketones in DMF solution were studied. At room temperature, 2-cyano-3-aryl-3-(1,2,3,4-tetrahydronaphthalen-1-one-2-yl) propionitrile derivatives were synthesized by the reaction between 2-arylmethylidene-1,2,3,4-tetra-hydronaphthalen-1-one and malononitrile. However, if the temperature was increased to 80℃, 2-amino-3-cyano-4-aryl-4H-benzo[h]chromene derivatives were obtained in high yields. When the α,β-unsaturated ketones were replaced by 2,6-biarylmethylidenecyclohexanone or 2,5-biarylmethylidenecyclopentanone, another series of 2-amino-3-cyano-4H-pyran derivatives was isolated successfully. The structures of the products were confirmed by X-ray diffraction analysis.

Michael‐Addition Reaction of Malononitrile with α,β‐Unsaturated Cycloketones Catalyzed by KF/Al2O3

A series of KF/Al₂O₃ catalyzed Michael‐addition reactions between malononitrile and α,β‐unsaturate cycloketones in DMF solution were studied. At room temperature, 2‐cyano‐3‐aryl‐3–(1, 2, 3, 4‐tetrahydronaphthalen‐1‐one‐2‐yl) propionitrile derivatives were synthesized by the reaction between 2‐arylmethylidene‐1, 2, 3, 4‐tetra‐hydronaphthalen‐l‐one and malononitrile. However, if the temperature was increased to 80 C, 2‐amino‐3‐cyano‐4‐aryl‐4H‐benzo[h]chromene derivatives were obtained in high yields. When the α,β‐unsaturated ketones were replaced by 2, 6‐biarylmethylidenecyclohexanone or 25‐biarylmethylidenecyclopentanone, another series of 2‐amino‐3‐cyano‐4H‐pyran derivatives was isolated successfully. The structures of the products were confirmed by X‐ray diffraction analysis.