1,1′-Ferrocene dicarboxylic acid pyridin-4-yl ester: A new bidentate ligand in arene ruthenium chemistry

Abstract

1,1′-Ferrocene dicarboxylic acid pyridin-4-yl ester ( 1) is prepared from 1,1′-ferrocene dicarbonyl chloride and 4-hydroxypyridine. This new bidentate ferrocenoyl ligand reacts with the monocationic complex [(η 6- p-cymene) 2Ru 2(μ-OH) 3] + to give the dicationic complex [(η 6- p-cymene) 2Ru 2(μ-OH) 2(1,1′- (NC 5H 4–OOC) 2–Fc)] 2+ ( 2) (Fc: C 5H 4–Fe–C 5H 4), isolated as a tetrafluoroborate salt. The single-crystal X-ray structure analysis of [ 2][BF 4] 2 reveals the ferrocenoyl pyridine ligand 1 to act as μ 2-η 2 chelating ligand in the dinuclear complex, having replaced a μ 2-η 1-hydroxo ligand.