Crystal structures and properties of catena-μ-nitrato (7-amino-5-aza-4-methyl-3-hepten-2-onato) copper(II) and μ₃-hydrox-otris(μ-8-amino-5-aza-4-methyl-3-octen-2-onato) tricopper(II) dinitrate

Abstract

The products of monocondensation of penta-2,4,-dione with 1,2-diaminoethane, HAE, and with 1,3-diaminopropane, HAT, react with copper nitrate hemipentahydrate to give catena-μ-nitrato (7-amino-5-aza-4-methyl-3-hepten-2-onato) copper(II), [Cu(AE)NO₃]_n and a mixture ofμ ₃-hydroxo-tris (μ-8-amino-5-aza-4-methyl-3-octen-2-onato) tricopper(II) dinitrate [Cu₃(AT)₃OH]-(NO₃)₂ and [Cu(AT)NO₃]_x, respectively. The structure of [Cu(AE)NO₃]_n has been determined from 1601 diffractometer data and refined by least squares methods toR=0.0306. The compound crystallizes in the monoclinic space groupP2₁/a witha=16.856(3)Å,b=8.109(4)Å,c=7.518(3)Å,β=90.15(2)°,D _c =1.725 g cm⁻³,D _o=1.72 g cm⁻³ andZ=4. Copper atoms in [Cu(AE)NO₃]_n are in a 4+1+1^* environment and are linked by the pseudobidentate and bridging nitrato group into infinite chains. The structure of [Cu₃(AT)₃OH](NO₃)₂ has been determined from 3178 diffractometer data and refined toR=0.0544. The compound crystallizes in the triclinic space groupP¯1 witha=11.918(2)Å,b=14.478(2)Å,c=11.501(3)Å,α=98.04(2)°,β=117.72(2)°, γ=99.80(1)°,D _c =1.580 g cm⁻³,D _o=1.59 g cm⁻³ andZ=2. The compound is associated in hexanuclear clusters due to hydrogen bonding interactions. Coordination about Cu is best described as square pyramidal. Magnetic susceptibility data indicate a weak antiferromagnetic exchange within the trinuclear core withJ=−14 cm⁻¹.