Hydrogenation of Esters to Alcohols Catalyzed by Defined Manganese Pincer Complexes

The first manganese‐catalyzed hydrogenation of esters to alcohols has been developed. The combination of Mn(CO)5Br with [HN(CH2CH2P(Et)2)2] leads to a mixture of cationic and neutral Mn PNP pincer complexes, which enable the reduction of various ester substrates, including aromatic and aliphatic esters as well as diesters and lactones. Notably, related pincer complexes with isopropyl or cyclohexyl substituents showed very low activity. A manganese‐catalyzed hydrogenation of esters to alcohols has been developed. The combination of Mn(CO)5Br with [HN(CH2CH2P(Et)2)2] led to a cationic and a neutral Mn PNP pincer complex, which both enable the reduction of various aromatic and aliphatic esters as well as diesters and lactones.