Syntheses and characterisation of tris(3-(pyridin-2-yl)-1H-pyrazol-1-yl)methane and its bis(µ-hydroxo) dicobalt(II) complex

Abstract

The new ligand tris(3-(pyridin-2-yl)-1H-pyrazol-1-yl)methane (HC(3-Pypz) 3 , 1) has been synthesised by the reaction of 2-(1H-pyrazol-3-yl)pyridine with CHCl 3 and Na 2 CO 3 under phasetransfer conditions. The reaction of HC(3-Pypz) 3 with Co(BF 4 ) 2 ·6 H 2 O leads to the formation of dinuclear bis(µ-hydroxo) cobalt(II) complex [Co 2 (µ-OH) 2 (HC(3-Pypz) 3 ) 2 ][BF 4 ] 2 ·2MeOH (2). This complex was crystallographically characterised. It comprises a Co 2 (µ-OH) 2 core with bridging hydroxide ligands. The tripodal tris-(3-(pyridine-2-yl)-1H-pyrazol-1-yl)methane ligands coordinate each cobalt atom with one bidentate arm, respectively. By this chelating and at the same time bridging coordination mode an octahedral coordination environment is formed.