A Dinuclear Nickel(II) Complex with Readily Accessible Coordination Sites and Additional N-Functional Groups in Proximity to the Bimetallic Core.

摘要: A series of pyrazolate-based dinuclear Ni(II) complexes relevant to the active site urease are reported. Deprotonation HL1 [HL1 = 3,5-bis(R2NCH2)-pyzH; R2N Me2N(CH2)3NMe] by means 1 equiv BuLi and subsequent reaction with 2 [Ni(H2O)6](ClO4)2 in presence NEtiPr2 affords complex [L1Ni2(OH)(MeCN)2](ClO4)2 (1). This is shown crystallographically contain two five-coordinate nickel ions bridged both pyrazolate a hydroxide, an acetonitrile solvent molecule bound each metal center. When HL2 employed {HL2 [Me2N(CH2)3]2N}, additional ligand side arms act as proton acceptors forming intramolecular N··H··N bridge yield [HL2Ni2(OH)(MeCN)2](ClO4)3 (2), whose basic bimetallic framework essentially identical 1. The centers exhibit strong antiferromagnetic coupling (J −46.7 cm-1). labile donors easily replaced either neutral ligands such dmf or ani...