A trinuclear copper(II) complex with 2,5-pyridine-dicarboxylato bridges – [Cu3(2,5-pydc)2(Me5dien)2(H2O)2(BF4)2]·H2O: Synthesis, crystal structure and magnetic properties

Abstract

A trinuclear copper(II) complex, [Cu 3 (2,5-pydc) 2 (Me 5 dien) 2 (BF 4 ) 2 (H 2 O) 2 ] · H 2 O 1 , has been constructed from 2,5-pyridine-dicarboxylato bridges (2,5-pydc 2− ) and N , N , N ′, N ″, N ″-pentamethyl-diethylenetriamine (Me 5 dien) acting as a blocking ligand. The copper ions, within the centrosymmetric trinuclear cations, are connected by two 2,5-pydc 2− bridges, with an intramolecular Cu···Cu separation of 8.432 A. The central copper ion exhibits an elongated octahedral geometry, with semicoordinated ( BF 4 - ) ions, while the terminal ones are pentacoordinated (distorted square-pyramidal geometry). The cryomagnetic investigation of 1 reveals an antiferromagnetic coupling of the copper(II) ions ( J = −5.9 cm −1 , H = − J S Cu1 S Cu2 − J S Cu2 S Cu1a ).