The reaction of acetone with [Cu(en)(2)](2+): The crystal structure of the copper(II)-beta-aminoketone complex initially formed and the kinetics of its base-catalysed conversion to the copper(II) complex of trans[14]dieneN(4)

The copper(II) complex of the beta-aminoketone 14-amino-4,4,9,11,11-pentamethyl-5,8,12-triazatetradec-8-en-2-one (L), [CuL](ClO4)(2) . MeCN has been prepared and its structure established by X-ray crystallography. C18H37N5O9Cl2Cu, triclinic, space group P (1) over bar, a = 10.752(9), b = 15.980(10), c = 8.112(7), alpha = 100.24(7), beta = 95.43(7), gamma = 93.54(6), V = 1361(1) Angstrom(3), Z = 2. In basic solution the complex undergoes base-catalysed ring closure to give the copper(II) complex of the macrocycle trans[14]dieneN(4). The kinetics of the ring closure reaction have been studied in detail Ring closure occurs by an intramolecular reaction involving the hydroxocomplex [CuLOH](+).