Mn(III)‐Based Oxidation of (Methylene)Bis(Cyclodiamide)s. Facile Synthesis of Tetraazadispiro‐(Undecanone)s and ‐(Tridecanone)s

Abstract

The oxidation of 5,5′‐(methylene)bis(6‐hydroxy‐1,3‐dimethylpyrimidine‐2,4(1H,3H)‐dione) monopiperidinium salts with Mn(OAc)3•2H2O was carried out in boiling MeCN, producing 2,4,9,11‐tetramethyl‐2,4,9,11‐tetraazadispiro[5.0.57.16]tridecane‐1,3,5,8,10,12‐hexaones in high yields. A similar reaction using 4,4′‐(methylene)bis(1,2‐diphenylpyrazolidine‐3,5‐dione)s gave 2,3,8,9‐tetraphenyl‐2,3,8,9‐tetraazadispiro[4.0.46.15]undecane‐1,4,7,10‐tetraones in good yields. The structure determination and the reaction mechanism for the formation of the unique tetraazadispiro(cyclopropane)s are discussed.