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Umpolung α-Silylation of Cyclopropyl Acetates via Low-Temperature Catalytic C-C Activation.

ABSTRACT: We report a redox-neutral, catalytic C-C activation of cyclopropyl acetates to produce silicon-containing five-membered heterocycles in a highly region-and chemoselective fashion. The umpolung α-selective silylation leading to dioxasilolanes is opposed to contemporary β-selective C-C functionalization protocols of cyclopropanols. Lewis base activation of dioxasilolanes as α-silyl carbinol equivalents undergoes the unconventional [1,2]-Brook rearrangement to form tertiary alcohols. Notably, mechanistic studies indicate that an electrophilic metal-π interaction harnessing highly fluorinated Tp (CF 3 ) 2 Rh(nbd) catalyst permitted a low-temperature C-C activation.

SUBMITTER: Avullala T

PROVIDER: S-EPMC6550485 | biostudies-literature | 2019 Jan

REPOSITORIES: biostudies-literature

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Umpolung α-Silylation of Cyclopropyl Acetates via Low-Temperature Catalytic C-C Activation.

Avullala Thirupataiah T Asgari Parham P Hua Yuanda Y Bokka Apparao A Ridlen Shawn G SG Yum Kyungsuk K Dias H V Rasika HVR Jeon Junha J

ACS catalysis 20181203 1

We report a redox-neutral, catalytic C-C activation of cyclopropyl acetates to produce silicon-containing five-membered heterocycles in a highly region-and chemoselective fashion. The umpolung α-selective silylation leading to dioxasilolanes is opposed to contemporary β-selective C-C functionalization protocols of cyclopropanols. Lewis base activation of dioxasilolanes as α-silyl carbinol equivalents undergoes the unconventional [1,2]-Brook rearrangement to form tertiary alc ...[more]

PMID: 31179157

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