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Helicene synthesis by Bronsted acid-catalyzed cycloaromatization in HFIP [(CF₃)₂CHOH].

ABSTRACT: A facile synthesis of carbo- and heterohelicenes was achieved via tandem cycloaromatization of bisacetal precursors, which were readily prepared through C-C bond formation by Suzuki-Miyaura coupling. This cyclization was efficiently realized by a catalytic amount of trifluoromethanesulfonic acid (TfOH) in a cation-stabilizing solvent, 1,1,1,3,3,3-hexafluoropropan-2-ol (HFIP), which readily allowed gram-scale syntheses of higher-order helicenes, double helical helicenes, and heterohelicenes.

SUBMITTER: Fujita T

PROVIDER: S-EPMC7884880 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Helicene synthesis by Brønsted acid-catalyzed cycloaromatization in HFIP [(CF3)2CHOH].

Fujita Takeshi T Shoji Noriaki N Yoshikawa Nao N Ichikawa Junji J

Beilstein journal of organic chemistry 20210209

A facile synthesis of carbo- and heterohelicenes was achieved via tandem cycloaromatization of bisacetal precursors, which were readily prepared through C-C bond formation by Suzuki-Miyaura coupling. This cyclization was efficiently realized by a catalytic amount of trifluoromethanesulfonic acid (TfOH) in a cation-stabilizing solvent, 1,1,1,3,3,3-hexafluoropropan-2-ol (HFIP), which readily allowed gram-scale syntheses of higher-order helicenes, double helical helicenes, and heterohelicenes. ...[more]

PMID: 33633807

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