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Catalytic Hydrogenation of Cyclic Carbonates using Manganese Complexes.

ABSTRACT: Catalytic hydrogenation of cyclic carbonates to diols and methanol was achieved using a molecular catalyst based on earth-abundant manganese. The complex [Mn(CO)2 (Br)[HN(C2 H4 Pi Pr2 )2 ] 1 comprising commercially available MACHO ligand is an effective pre-catalyst operating under relatively mild conditions (T=120?°C, p(H2 )=30-60?bar). Upon activation with NaOt Bu, the formation of coordinatively unsaturated complex [Mn(CO)2 [N(C2 H4 Pi Pr2 )2 )] 5 was spectroscopically verified, which confirmed a kinetically competent intermediate. With the pre-activated complex, turnover numbers up to 620 and 400 were achieved for the formation of the diol and methanol, respectively. Stoichiometric reactions under catalytically relevant conditions provide insight into the stepwise reduction form the CO2 level in carbonates to methanol as final product.

SUBMITTER: Kaithal A

PROVIDER: S-EPMC6221167 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Catalytic Hydrogenation of Cyclic Carbonates using Manganese Complexes.

Kaithal Akash A Hölscher Markus M Leitner Walter W

Angewandte Chemie (International ed. in English) 20180912 41

Catalytic hydrogenation of cyclic carbonates to diols and methanol was achieved using a molecular catalyst based on earth-abundant manganese. The complex [Mn(CO)2 (Br)[HN(C2 H4 Pi Pr2 )2 ] 1 comprising commercially available MACHO ligand is an effective pre-catalyst operating under relatively mild conditions (T=120 °C, p(H2 )=30-60 bar). Upon activation with NaOt Bu, the formation of coordinatively unsaturate ...[more]

PMID: 30134081

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