Department of Chemistry, Dalhousie University, 6274 Coburg Road, P.O. Box 15000, Halifax, Nova Scotia, B3H 4R2, Canada.
Chemistry. 2023 Feb 1;29(7):e202203394. doi: 10.1002/chem.202203394. Epub 2022 Dec 8.
A systematic competitive evaluation of the DalPhos ligand family in nickel-catalyzed N-arylation chemistry is reported, involving primary (linear and branched) and secondary alkylamines, as well as a primary five-membered heteroarylamine (aminopyrazole), in combination with a diverse set of test electrophiles and bases (NaOtBu, K CO , DBU/NaTFA). In addition to providing optimal ligand/catalyst identification, and bringing to light methodology limitations (e. g., unwanted C-O cross-coupling with NaOtBu), our survey enabled the development of the first efficient catalyst system for heteroatom-dense C-N cross-coupling of aminopyrazoles and related nucleophiles with (hetero)aryl chlorides by use of an amine 'dual-base' system.
本文对 DalPhos 配体家族在镍催化 N-芳基化反应中的应用进行了系统的竞争评估，涉及伯（直链和支链）和仲烷基胺，以及一个伯五元杂芳基胺（氨基吡唑），与一系列不同的测试亲电试剂和碱（NaOtBu、KCO 3 、DBU/NaTFA）相结合。除了提供最佳的配体/催化剂鉴定，并揭示方法学限制（例如，与 NaOtBu 发生不需要的 C-O 交叉偶联）外，我们的研究还开发了第一个有效的催化剂体系，用于通过使用胺“双碱”体系，实现氨基吡唑和相关亲核试剂与（杂）芳基氯化物的富杂原子 C-N 交叉偶联。
