Solvothermal synthesis of enneanuclear [CuLn] clusters.

Employment of H3L (= 2-(beta-naphthalideneamino)-2-hydroxymethyl-1-propanol) in mixed-metal copper-lanthanide cluster chemistry has led to the isolation of four new enneanuclear heteronuclear isostructural [Cu(7)(II)Ln(2)(III)] complexes. More specifically, the solvothermal reaction of Cu-2(OAc)(4)center dot 2H(2)O with H3L and the corresponding lanthanide nitrate salt in MeCN in the presence of a base, NEt3, yielded three complexes with the general formula [Cu(7)(II)Ln(2)(III) (L)(4)(HL)(2)(OAc)(4)]center dot 2MeCN (Ln: Gd, 1.2MeCN; Tb, 2.2MeCN; Dy, 3.2MeCN), while in addition the Y-III analogue, [(Cu7Y2III)-Y-II(L)(4)(HL)(2)(OAc)(4)]center dot 2MeCN (4.2MeCN), was also synthesized in the same manner. The structure of the cluster describes two corner-sharing [Cu(3)Ln] cubane metallic units, each one further connected to one Cu-II ion. Dc magnetic susceptibility studies in the 5-300 K range for complexes 1-4 reveal the presence of both ferromagnetic and antiferromagnetic exchange interactions within the metallic clusters.