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Et3B-mediated two- and three-component coupling reactions via radical decarbonylation of α-alkoxyacyl tellurides: single-step construction of densely oxygenated carboskeletons.

ABSTRACT: The single-step construction of various densely oxygenated carboskeletons was achieved by radical-based two- and three-component coupling reactions of sugar derivatives, without the need for light or heat. Et3B/O2-mediated decarbonylation readily converted α-alkoxyacyl tellurides to α-alkoxy carbon radicals, which intermolecularly added to glyoxylic oxime ether or enones to provide the two-component adducts. Furthermore, the three-component adducts were produced by an intermolecular aldol reaction between the aldehyde and the boron enolates generated by capture of the two-component radical intermediates by Et3B. This powerful coupling method serves as a novel strategy for the convergent synthesis of polyol natural products.

SUBMITTER: Nagatomo M

PROVIDER: S-EPMC5763990 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Et3B-mediated two- and three-component coupling reactions via radical decarbonylation of α-alkoxyacyl tellurides: single-step construction of densely oxygenated carboskeletons.

Nagatomo Masanori M Kamimura Daigo D Matsui Yuki Y Masuda Keisuke K Inoue Masayuki M

Chemical science 20150306 5

The single-step construction of various densely oxygenated carboskeletons was achieved by radical-based two- and three-component coupling reactions of sugar derivatives, without the need for light or heat. Et3B/O2-mediated decarbonylation readily converted α-alkoxyacyl tellurides to α-alkoxy carbon radicals, which intermolecularly added to glyoxylic oxime ether or enones to provide the two-component adducts. Furthermore, the three-component adducts were produced by an inter ...[more]

PMID: 29403632

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