Cyclam

Metal complexes of cyclam are prone to oxidative degradation, which is initiated by deprotonation of the secondary amine. This flaw led to the development of cyclam derivatives wherein the NH centres are replaced by tertiary amines. For example, the tetramethyl derivatives (tetramethylcyclam, tmc) are readily prepared by methylation using formaldehyde and formic acid (Eschweiler–Clarke reaction). These oxidatively robust derivatives of cyclam have enabled a number of metal–O2 complexes. ==See also==