Isolation of a stable binuclear copper complex containing a copper–copper bonded unit. X-Ray structure determination of {(7,8,15,16,17,18,25,26,33,34,35,36-dodecahydrotetrabenzo[e,m,s,a′][1,4,8,11,15,18,22,25]octaazacyclo-octacosine)dicopper} triperchlorate

Abstract

The X-ray crystal structure of the title octaazamacrocycle with a 28-membered ring shows that it is capable of incorporating a symmetrical copper–copper bonded unit which contains a short Cu–Cu bond [2·445(4)Å]; the compound is paramagnetic with µ_eff= 1·87 µ_B at 300 K, exhibiting a single line at g= 2·09 in the X-band e.s.r. spectra of solid samples or of frozen acetonitrile solutions (77 K).