CuI/Oxalamide Catalyzed Couplings of (Hetero)aryl Chlorides and Phenols for Diaryl Ether Formation

• Published in: Angewandte Chemie (International ed.) Vol. 55; no. 21; pp. 6211 - 6215
• Main Authors: Fan, Mengyang, Zhou, Wei, Jiang, Yongwen, Ma, Dawei
• Format: Journal Article
• Language: English
• Published: WEINHEIM Blackwell Publishing Ltd 17.05.2016; Wiley; Wiley Subscription Services, Inc
• Edition: International ed. in English
• Subjects: (hetero)aryl chlorides; Aromatic compounds; biaryl ethers; Chemistry; Chemistry, Multidisciplinary; Chlorides; copper; Couplings; cross-coupling; Diaryl ethers; Electrons; ligand screen; Ligands; Phenols; Physical Sciences; Science & Technology; Substitutes; HALIDES; PALLADIUM; C-O BOND; ARYLATION; (hetero)aryl chlorides; biaryl ethers; MILD; VERSATILE; PRODUCTS; cross-coupling; copper; ligand screen; LIGAND; EFFICIENT; ARYL CHLORIDES
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201601035

Couplings between (hetero)aryl chlorides and phenols can be effectively promoted by CuI in combination with an N‐aryl‐N′‐alkyl‐substituted oxalamide ligand to proceed smoothly at 120 °C. For this process, N‐aryl‐N′‐alkyl‐substituted oxalamides are more effective ligands than bis(N‐aryl)‐substituted oxalamides. A wide range of electron‐rich and electron‐poor aryl and heteroaryl chlorides gave the corresponding coupling products in good yields. Satisfactory conversions were achieved with electron‐rich phenols as well as a limited range of electron‐poor phenols. Catalyst and ligand loadings as low as 1.5 mol % are sufficient for the scaled‐up variants of some of these reactions. Aryl and alkyl: N‐Aryl‐N′‐alkyl‐substituted oxalamide ligands promote the CuI catalyzed coupling of (hetero)aryl chlorides and phenols at 120 °C more effectively than bis(N‐aryl)‐substituted oxalamides. A wide range of electron‐rich and electron‐poor aryl and heteroaryl chlorides were converted into the corresponding coupling products in good yields.