Electrocatalytic hydrogen generation by a trithiolato-bridged dimanganese hexacarbonyl anion with a turnover frequency exceeding 40,000 s(-1).

An unusual ionic manganese model complex [Mn(bpy)3](+)[(CO)3Mn(µ-SPh)3Mn(CO)3](-)(bpy: 2,2'-bipyridine) has been synthesized, which bears some structural resemblance to the active site of [FeFe] hydrogenase. An overpotential of 0.61 V has been determined for the electrocatalytic proton reduction using this complex in CH3CN with CF3COOH as the proton source. A turnover frequency of 44,600 s(-1) is achieved at high scan rates and in the presence of a large amount of acid.