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. 2022 Jan 7;87(1):683-692.
doi: 10.1021/acs.joc.1c02685. Epub 2021 Dec 21.

Propargylation of CoQ0 through the Redox Chain Reaction

Robert Pawlowski  1 , Maciej Stodulski  1 , Jacek Mlynarski  1
Affiliations

Propargylation of CoQ0 through the Redox Chain Reaction

Robert Pawlowski et al. J Org Chem. .

Abstract

An efficient catalytic propargylation of CoQ0 is described by employing the cooperative effect of Sc(OTf)3 and Hantzsch ester. It is suggested to work through the redox chain reaction, which involves hydroquinone and dimeric propargylic moiety intermediates. A broad range of propargylic alcohols can be converted into the appropriate derivatives of CoQ0 containing triple bonds in good to excellent yields. The mechanism of the given transformation is also discussed.

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Conflict of interest statement

The authors declare no competing financial interest.

Figures

Scheme 1
Scheme 1. Direct Propargylation of CoQ0 by Various Propargyl Derivatives
Unless otherwise indicated, all reactions were performed as follows: reaction scale: 0.15 mmol, 10 mol % of catalyst, HE 5 mol %, Ar, MeCN 1 mL, 60 °C, reaction time 24 h.
Scheme 2
Scheme 2. Direct Propargylation of CoQ0 by Various Propargyl Derivatives
Unless otherwise indicated, all reactions were performed as follows: reaction scale: 0.15 mmol, 10 mol % of catalyst, HE 5 mol %, Ar, MeCN 1 mL, 60 °C, reaction time 24 h.
Scheme 3
Scheme 3. Control Experiments for the Propargylation of CoQ0
Unless otherwise indicated, all reactions were performed as follows: reaction scale: 0.15 mmol, 10 mol % of catalyst, HE 5 mol %, Ar, MeCN 1 mL, temp. 60 °C, reaction time 24 h; isolated yields.
Scheme 4
Scheme 4. Proposed Reaction Mechanism for the Propargylation of CoQ0
See this image and copyright information in PMC

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