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Electro-Mechanochemical Atom Transfer Radical Cyclizations using Piezoelectric BaTiO₃.

ABSTRACT: The formation and regeneration of active Cu^I species is a fundamental mechanistic step in copper-catalyzed atom transfer radical cyclizations (ATRC). Typically, the presence of the catalytically active Cu^I species in the reaction mixture is secured by using high Cu^I catalyst loadings or the addition of complementary reducing agents. In this study it is demonstrated how the piezoelectric properties of barium titanate (BaTiO₃ ) can be harnessed by mechanical ball milling to induce electrical polarization in the strained piezomaterial. This strategy enables the conversion of mechanical energy into electrical energy, leading to the reduction of a Cu^II precatalyst into the active Cu^I species in copper-catalyzed mechanochemical solvent-free ATRC reactions.

SUBMITTER: Schumacher C

PROVIDER: S-EPMC7540587 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Electro-Mechanochemical Atom Transfer Radical Cyclizations using Piezoelectric BaTiO3.

Schumacher Christian C Hernández José G JG Bolm Carsten C

Angewandte Chemie (International ed. in English) 20200709 38

The formation and regeneration of active CuI species is a fundamental mechanistic step in copper-catalyzed atom transfer radical cyclizations (ATRC). Typically, the presence of the catalytically active CuI species in the reaction mixture is secured by using high CuI catalyst loadings or the addition of complementary reducing agents. In this study it is demonstrated how the piezoelectric properties of barium titanate (BaTiO3 ) can be harnessed by mechan ...[more]

PMID: 32515540

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