Synthesis of 2,9‐diacyl‐1, 10‐phenanthrolines

Abstract

Abstract A convenient high yield synthetic route leading to 2,9‐diacyl‐1,10‐phenanthrolines has been developed. The reaction of bis‐amide 1 with 2‐pyridyllithium, 6‐bromo‐2‐pyridyllithium or 2‐thienyllithium led to the diacyl compounds 5,6 and 7 , respectively. Attempts to prepare 8 by intramolecular coupling of 6 or by treatment of 1 with dilithio analogue 9b were unsuccessful. Treatment of 1 with butyllithium or aryllithium reagents led to 10a, 10b and 10c.