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MOF-808 as a Highly Active Catalyst for the Diastereoselective Reduction of Substituted Cyclohexanones.

ABSTRACT: Zr-containing MOF-808 is an excellent heterogeneous catalyst for the diastereoselective Meerwein-Ponndorf-Verley reduction of substituted cyclohexanones. The presence of substituents at the 2 or 3 position of the cyclohexanone ring strongly drives the reaction towards the formation of one of the two possible isomers. For 3-methyl cyclohexanone, the available space inside the MOF pores allows the formation of the bulkier transition state leading to the thermodynamically stable 3-cis-cyclohexanol. For 2-methyl cyclohexanone, the reaction rate is much slower and the final diastereoselectivity depends on the size of the alcohol used. Finally, reduction of 2-phenyl cyclohexanone is considerable faster over MOF-808 than for any other catalyst reported so far. The large size of the phenyl favors the selective formation (up to 94% selectivity) of the cis-alcohol, which goes through a less hindered transition state.

SUBMITTER: Mautschke HH

PROVIDER: S-EPMC9571754 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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MOF-808 as a Highly Active Catalyst for the Diastereoselective Reduction of Substituted Cyclohexanones.

Mautschke Hans Hilmar HH Llabrés I Xamena Francesc X FX

Molecules (Basel, Switzerland) 20220925 19

Zr-containing MOF-808 is an excellent heterogeneous catalyst for the diastereoselective Meerwein-Ponndorf-Verley reduction of substituted cyclohexanones. The presence of substituents at the 2 or 3 position of the cyclohexanone ring strongly drives the reaction towards the formation of one of the two possible isomers. For 3-methyl cyclohexanone, the available space inside the MOF pores allows the formation of the bulkier transition state leading to the thermodynamically stable 3-<i>cis</i>-cycloh ...[more]

PMID: 36234853

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