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Homogeneous Sc(OTf)₃-Catalyzed Direct Allylation Reactions of General Alcohols with Allylsilanes.

ABSTRACT: Homogeneous Sc(OTf)₃ used in nitromethane showed excellent catalytic activity for the direct allylation reactions of general alcohols including benzylic, propargylic, allylic, and some aliphatic alcohols with allyltrimethylsilane under mild and neutral reaction conditions. Metal-free β-silyl-substituted carbocations are intermediates generated by the highly oxophilic Sc(OTf)₃-assisted rapid removal of a hydroxyl group in alcohols, which is supported by the result that allylation of (R)-1-(naphthalen-2-yl)ethan-1-ol with allytrimethylsilanes using the Sc(OTf)₃ catalyst combined with (R)- or (S)-[1,1'-binaphthalene]-2,2'-diol ligands gave only racemic 2-(pent-4-en-2-yl)naphthalene in quantitative yield. The present study resolves the argument about the uncertain catalytic activity of Sc(OTf)₃.

SUBMITTER: Di Y

PROVIDER: S-EPMC6643996 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature

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Homogeneous Sc(OTf)3-Catalyzed Direct Allylation Reactions of General Alcohols with Allylsilanes.

Di Yuanjun Y Yoshimura Tsutomu T Naito Shun-Ichi SI Kimura Yu Y Kondo Teruyuki T

ACS omega 20181231 12

Homogeneous Sc(OTf)3 used in nitromethane showed excellent catalytic activity for the direct allylation reactions of general alcohols including benzylic, propargylic, allylic, and some aliphatic alcohols with allyltrimethylsilane under mild and neutral reaction conditions. Metal-free β-silyl-substituted carbocations are intermediates generated by the highly oxophilic Sc(OTf)3-assisted rapid removal of a hydroxyl group in alcohols, which is supported by the result that allyl ...[more]

PMID: 31458450

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