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Comparing Neutral (Monometallic) and Anionic (Bimetallic) Aluminum Complexes in Hydroboration Catalysis: Influences of Lithium Cooperation and Ligand Set.

ABSTRACT: Bimetallic lithium aluminates and neutral aluminum counterparts are compared as catalysts in hydroboration reactions with aldehydes, ketones, imines and alkynes. Possessing Li-Al cooperativity, ate catalysts are found to be generally superior. Catalytic activity is also influenced by the ligand set, alkyl and/or amido. Devoid of an Al-H bond, iBu2 Al(TMP) operates as a masked hydride reducing benzophenone through a ?-? transfer process. This catalyst library therefore provides an entry point into the future design of Al catalysts targeting substrate specific transformations.

SUBMITTER: Pollard VA

PROVIDER: S-EPMC6099445 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Comparing Neutral (Monometallic) and Anionic (Bimetallic) Aluminum Complexes in Hydroboration Catalysis: Influences of Lithium Cooperation and Ligand Set.

Pollard Victoria A VA Fuentes M Ángeles MÁ Kennedy Alan R AR McLellan Ross R Mulvey Robert E RE

Angewandte Chemie (International ed. in English) 20180709 33

Bimetallic lithium aluminates and neutral aluminum counterparts are compared as catalysts in hydroboration reactions with aldehydes, ketones, imines and alkynes. Possessing Li-Al cooperativity, ate catalysts are found to be generally superior. Catalytic activity is also influenced by the ligand set, alkyl and/or amido. Devoid of an Al-H bond, iBu<sub>2</sub> Al(TMP) operates as a masked hydride reducing benzophenone through a β-Η transfer process. This catalyst library therefore provides an entr ...[more]

PMID: 29906339

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