, 358 (1993). The crystal structures of N, N'-di(2-acetylcyclohexenyl)ethylenediamine (L,) and its copper(I1) complex, which crystallizes with one solvent molecule of chloroform (Cu(L,-2H). CHC13), were determined. Crystallographic details are as follows: L, is monoclinic, space group P2,/c, with a = 8.280(2), b = 1 1.692(2), and c = 9.355(2) A, P = 1 14.10(2)", V = 826.7(3) A~, Z = 2; p, = 1.22 g cm-j, k(Cu Ka) = 5.93 cm-I, with the final residual indices of R = 0.046 and R,,. = 0.070 for 991sunique reflections. Cu(L,-2H). CHCI3 is triclinic, space group P I , with a = 1 1.121(3), b = 11.713(3), and c = 8.974(2) A, cu = 99.35(2)", P = 110.83(2)", y = 82.33(2)", V = 1074(1) A~, Z = 2; p, = 1.50 g c K 3 , ~( C U Ka) = 50.74 cm-I, with the final residual indices of R = 0.048 and R,,. = 0.077 for 2369 unique reflections. The X-ray diffraction study shows that in the crystal state the ligand L, is in the methylketone-cyclohexanonenamine isomeric form. For the copper complex Cu(LI-2H). CHCI,, the geometry around the metal atom is distorted square planar, and the angle between the chelate ring planes in the complex is 15. lo. An NMR study shows that L, in solution has the same structure as that observed in the solid state by X-ray diffraction. [Traduit par la redaction]