The reactions of Cu(NO3)2.3H2O with pyridazine (pydz) in water and ethanol solutions have been investigated. In water, using a 1:1 salt: pydz molar ratio, the polymeric species catena-[Cu(mu-eta2-pydz)(mu-OH)(mu-O2NO)].H2O 1 was obtained, whilst with a ratio of 1:2 the trinuclear complex (Cu3(mu-eta2-pydz)4(pydz)2(mu-NO3)2(NO3)4] 2 was isolated. In ethanol a different species 3, not yet characterized, was obtained on employing a ratio of 1:1. With a salt: pydz molar ratio close to 1 :2 the trinuclear species 2 was recovered through a cleaner reaction, while, when a ratio of ca. 1:3 was used the mononuclear complex [Cu(pydz)3(O2NO)(NO3)] 4 was obtained. The structures of compounds 1 and 2 have been characterized by single-crystal X-ray analysis: 1, monoclinic, space group I2/m (no. 12), a = 10.239(1), b = 6.643(1), c = 12.363(2) angstrom, beta = 103.74(1)-degrees, Z = 4, R = 0.022 for 651 [F(o) > 4sigma(F(o)] reflections; 2, monoclinic. space group P2(1)/n (no. 14), a = 8.957(2), b = 13.687(4), c = 14.945(4) angstrom, beta = 96.06(2)-degrees, Z = 2, R = 0.038 for 2430 [F(o) > 4sigma(F(o))] reflections. Compound 1 is a linear polymer [Cu ... Cu 3.3215(5) angstrom], with each metal atom pair symmetrically bridged by a eta2-pydz molecule, a hydroxide group and a nitrate. Compound 2 contains a linear trinuclear centrosymmetric array of copper atoms, with the two equivalent Cu...Cu interactions [3.4057(8) angstrom] symmetrically bridged by two eta2-pydz molecules and a nitrate. Both 1 and 2 exhibit strong exchange coupling between the copper atoms, the room-temperature mu(eff) being reduced to 1.08 1 and 2.62 mu(B) 2.
Carlucci, L., Ciani, G., Moret, M., Sironi, A. (1994). REACTIONS OF COPPER(II) NITRATE WITH PYRIDAZINE (PYDZ) AND CRYSTAL-STRUCTURES OF CATENA-[CU(MU-ETA(2)-PYDZ)(MU-OH)(MU-O2NO)]CENTER-DOT-H2O AND [CU3(MU-ETA(2)-PYDZ)4(PYDZ)2(MU-NO3)2(NO3)4]. JOURNAL OF THE CHEMICAL SOCIETY DALTON TRANSACTIONS(16), 2397-2404 [10.1039/dt9940002397].
REACTIONS OF COPPER(II) NITRATE WITH PYRIDAZINE (PYDZ) AND CRYSTAL-STRUCTURES OF CATENA-[CU(MU-ETA(2)-PYDZ)(MU-OH)(MU-O2NO)]CENTER-DOT-H2O AND [CU3(MU-ETA(2)-PYDZ)4(PYDZ)2(MU-NO3)2(NO3)4]
MORET, MASSIMO;
1994
Abstract
The reactions of Cu(NO3)2.3H2O with pyridazine (pydz) in water and ethanol solutions have been investigated. In water, using a 1:1 salt: pydz molar ratio, the polymeric species catena-[Cu(mu-eta2-pydz)(mu-OH)(mu-O2NO)].H2O 1 was obtained, whilst with a ratio of 1:2 the trinuclear complex (Cu3(mu-eta2-pydz)4(pydz)2(mu-NO3)2(NO3)4] 2 was isolated. In ethanol a different species 3, not yet characterized, was obtained on employing a ratio of 1:1. With a salt: pydz molar ratio close to 1 :2 the trinuclear species 2 was recovered through a cleaner reaction, while, when a ratio of ca. 1:3 was used the mononuclear complex [Cu(pydz)3(O2NO)(NO3)] 4 was obtained. The structures of compounds 1 and 2 have been characterized by single-crystal X-ray analysis: 1, monoclinic, space group I2/m (no. 12), a = 10.239(1), b = 6.643(1), c = 12.363(2) angstrom, beta = 103.74(1)-degrees, Z = 4, R = 0.022 for 651 [F(o) > 4sigma(F(o)] reflections; 2, monoclinic. space group P2(1)/n (no. 14), a = 8.957(2), b = 13.687(4), c = 14.945(4) angstrom, beta = 96.06(2)-degrees, Z = 2, R = 0.038 for 2430 [F(o) > 4sigma(F(o))] reflections. Compound 1 is a linear polymer [Cu ... Cu 3.3215(5) angstrom], with each metal atom pair symmetrically bridged by a eta2-pydz molecule, a hydroxide group and a nitrate. Compound 2 contains a linear trinuclear centrosymmetric array of copper atoms, with the two equivalent Cu...Cu interactions [3.4057(8) angstrom] symmetrically bridged by two eta2-pydz molecules and a nitrate. Both 1 and 2 exhibit strong exchange coupling between the copper atoms, the room-temperature mu(eff) being reduced to 1.08 1 and 2.62 mu(B) 2.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.