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Aryne cycloaddition reactions of benzodioxasilines as aryne precursors generated by catalytic reductive ortho-C-H silylation of phenols with traceless acetal directing groups.

ABSTRACT: Diversely substituted arylsilyl triflates, as aryne precursors for aryne cycloaddition reactions, were accessed from benzodioxasilines. Catalytic reductive C-H ortho-silylation of phenols with traceless acetal directing groups was exploited to prepare benzodioxasilines. Sequential addition of MeLi and then trifluoromethanesulfonic anhydride to benzodioxasilines provided arylsilyl triflates in a single pot. Notably, this approach was successfully utilized to prepare sterically hindered 1,2,3-trisubstituted arylsilyl triflates, which ultimately underwent fluoride-mediated aryne cycloaddition.

SUBMITTER: Asgari P

PROVIDER: S-EPMC5501486 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Aryne cycloaddition reactions of benzodioxasilines as aryne precursors generated by catalytic reductive ortho-C-H silylation of phenols with traceless acetal directing groups.

Asgari Parham P Dakarapu Udaya Sree US Nguyen Hiep H HH Jeon Junha J

Tetrahedron 20161208 29

Diversely substituted arylsilyl triflates, as aryne precursors for aryne cycloaddition reactions, were accessed from benzodioxasilines. Catalytic reductive C-H ortho-silylation of phenols with traceless acetal directing groups was exploited to prepare benzodioxasilines. Sequential addition of MeLi and then trifluoromethanesulfonic anhydride to benzodioxasilines provided arylsilyl triflates in a single pot. Notably, this approach was successfully utilized to prepare sterically hindered 1,2 ...[more]

PMID: 28694551

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