Di-μ-olato dinuclear copper(II) compounds. The structure of bis-μ-O-[(4,6,6-trimethyl-9-(pyridin-2-yl)-3,7-diazanon-3-en-1-olato)copper(II)] perchlorate

Abstract

Preparations are reported for blue-green[{Cu(pyen)(eto)}₂](ClO₄)₂[pyen is 2-(2-aminoethyl)pyridine, eto^– isdeprotonated 2-aminoethanol] and of green[{Cu(pyaceto)}₂](ClO₄)₂,formed by reaction of this compound with acetone[pyaceto^– is deprotonated4,6,6-trimethyl-9-(pyridin-2-yl)-3,7-diazanon-3-en-1-ol]. The structureof[{Cu(pyaceto)}₂](ClO₄)₂shows a unit cell containing two independent, but closely similar,centrosymmetrical dinuclear diolato-bridged cations. The copper(II) ions arein square pyramidal coordination, with the two bridging oxygen atoms, and theimine and secondary amine nitrogen atoms in the basal plane, with the pyridinenitrogen atom more weakly coordinated axially. Mean dimensions for the twocations are Cu–Cu# 2.99, Cu–N_basal 2.01,Cu–O 1.96, Cu–N_axial 2.24 Å,O–Cu–O# 99, Cu–O–Cu# 81, C–O–Cu110, C–O–Cu# 130˚[C₃₀H₄₆Cl₂Cu₂N₆O₁₀,monoclinic, space group P21/n, a 13.487(1),b 13.356(1), c 20.921(2) Å,β 103.235(3)˚, R1 = 0.0516 for 4694reflections]. Magnetic susceptibilities (100–300 K) showantiferromagnetic spin coupling for[{Cu(pyaceto)}₂](ClO₄)₂and[{Cu(pyen)(eto)}₂](ClO₄)₂with singlet–triplet level separation J of–110(10) and –65(10) cm^–1,respectively, indicating that[{Cu(pyen)(eto)}₂](ClO₄)₂also has a dinuclear structure.