meso-(5,7,7,12,14,14-Hexamethyl-1,4,8,11-tetraazacyclotetradec-4,11-diene)copper(II) perchlorate; an unexpected preparation and structure determination

Reduction of (4,6,6-trimethyl-3,7-diaza-non-3-en-1,9-diamine)copper(II) perchlorate in water by NaBH4, followed by air oxidation, formed (5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotertradec-4,11-diene)copper(II) perchlorate, for which the structure was determined, showing the meso-configuration of the square-planar coordinated copper(II) cation.