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Synlett 2025; 36(11): 1498-1501
DOI: 10.1055/a-2566-7550
letter

Ligand-Promoted Palladium(II)-Catalyzed ortho-Hydroxylation of Masked Benzyl Alcohols

Ke-Yang Huang
,
Ze-Yu Wu
,
Jun Luo  ∗
,
Chao Jiang  ∗

This work was supported by the National Natural Science Foundation of China (NSFC) (Grants Nos. 21772092 and 22075144).
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Abstract

A PdII-catalyzed ortho-C(sp²)–H hydroxylation of benzyl alcohols using an oxime ether as a monodentate directing group was developed. An N-acetylglycine ligand, in facilitating the cleavage of a C–H bond, is crucial to the reaction. The reaction might involve the formation of hydroxyl radicals generated from Oxone, and a six-membered exo-palladacycle intermediate is proposed. Various substituents on the phenyl ring were tolerated in the reaction. A gram-scale reaction and directing-group removal were also performed, demonstrating the applicability of the reaction in syntheses of salicyl alcohols.

Key words

C(sp2)–H hydroxylation - palladium-catalysis - benzylic alcohols - oxime ethers - phenolic compounds

Supporting Information

    Supporting information for this article is available online at https://doi-org.accesdistant.sorbonne-universite.fr/10.1055/a-2566-7550.
  • Supporting Information


Publication History

Received: 21 February 2025

Accepted after revision: 25 March 2025

Accepted Manuscript online:
25 March 2025

Article published online:
09 May 2025

© 2025. Thieme. All rights reserved

Georg Thieme Verlag KG
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