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Hydrogenation of benzoic acid derivatives over Pt/TiO₂ under mild conditions.

ABSTRACT: Hydrogenation of benzoic acid (BA) to cyclohexanecarboxylic acid (CCA) has important industrial and academic significance, however, the electron deficient aromatic ring and catalyst poisoning by carboxyl groups make BA hydrogenation a challenging transformation. Herein, we report that Pt/TiO₂ is very effective for BA hydrogenation with, to our knowledge, a record TOF of 4490 h^-1 at 80 °C and 50 bar H₂, one order higher than previously reported results. Pt/TiO₂ catalysts with electron-deficient and electron-enriched Pt sites are obtained by modifying the electron transfer direction between Pt and TiO₂. Electron-deficient Pt sites interact with BA more strongly than electron-rich Pt sites, helping the dissociated H of the carboxyl group to participate in BA hydrogenation, thus enhancing its activity. The wide substrate scope, including bi- and tri-benzoic acids, further demonstrates the high efficiency of Pt/TiO₂ for hydrogenation of BA derivatives.

SUBMITTER: Guo M

PROVIDER: S-EPMC9814562 | biostudies-literature | 2021 Apr

REPOSITORIES: biostudies-literature

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Hydrogenation of benzoic acid derivatives over Pt/TiO2 under mild conditions.

Guo Miao M Kong Xiangtao X Li Chunzhi C Yang Qihua Q

Communications chemistry 20210416 1

Hydrogenation of benzoic acid (BA) to cyclohexanecarboxylic acid (CCA) has important industrial and academic significance, however, the electron deficient aromatic ring and catalyst poisoning by carboxyl groups make BA hydrogenation a challenging transformation. Herein, we report that Pt/TiO2 is very effective for BA hydrogenation with, to our knowledge, a record TOF of 4490 h-1 at 80 °C and 50 bar H2, one order higher than previously reported results. Pt/TiO<sub ...[more]

PMID: 36697567

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