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Improved Process for the Palladium-Catalyzed C-O Cross-Coupling of Secondary Alcohols.

ABSTRACT: An improved protocol for the Pd-catalyzed C-O cross-coupling of secondary alcohols is described. The use of biaryl phosphine L2 as the ligand was key to achieving efficient cross-coupling of (hetero)aryl chlorides with only a 20% molar excess of the alcohol. Additionally, we observed an unusual reactivity difference between an electron-rich aryl bromide and the analogous aryl chloride, and deuterium-labeling suggested that currently unidentified pathways for reduction play an important role in explaining this disparity.

SUBMITTER: Zhang H

PROVIDER: S-EPMC8025245 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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Improved Process for the Palladium-Catalyzed C-O Cross-Coupling of Secondary Alcohols.

Zhang Hong H Ruiz-Castillo Paula P Schuppe Alexander W AW Buchwald Stephen L SL

Organic letters 20200624 14

An improved protocol for the Pd-catalyzed C-O cross-coupling of secondary alcohols is described. The use of biaryl phosphine <b>L2</b> as the ligand was key to achieving efficient cross-coupling of (hetero)aryl chlorides with only a 20% molar excess of the alcohol. Additionally, we observed an unusual reactivity difference between an electron-rich aryl bromide and the analogous aryl chloride, and deuterium-labeling suggested that currently unidentified pathways for reduction play an important ro ...[more]

PMID: 32579375

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