Room-Temperature Amination of Chloroheteroarenes in Water by a Recyclable Copper(II)-Phosphaadamantanium Sulfonate System
作者:Udaysinh Parmar、Dipesh Somvanshi、Santosh Kori、Aman A. Desai、Rambabu Dandela、Dilip K. Maity、Anant R. Kapdi
DOI:10.1021/acs.joc.1c00845
日期:2021.7.2
Buchwald–Hartwig amination of chloroheteroarenes has been a challenging synthetic process, with very few protocols promoting this important transformation at ambient temperature. The current report discusses about an efficient copper-based catalyticsystem (Cu/PTABS) for the amination of chloroheteroarenes at ambient temperature in water as the sole reaction solvent, a combination that is first to
AbstractA new class of large‐but‐flexible Pd‐BIAN‐NHC catalysts (BIAN=acenaphthoimidazolylidene, NHC=N‐heterocyclic carbene) has been rationally designed to enable the challenging Buchwald‐Hartwig amination of coordinating heterocycles. This robust class of BIAN‐NHC catalysts permits cross‐coupling under practical aerobic conditions of a variety of heterocycles with aryl, alkyl, and heteroarylamines, including historically challenging oxazoles and thiazoles as well as electron‐deficient heterocycles containing multiple heteroatoms with BIAN‐INon (N,N′‐bis(2,6‐di(4‐heptyl)phenyl)‐7H‐acenaphtho[1,2‐d]imidazol‐8‐ylidene) as the most effective ligand. Studies on the ligand structure and electronic properties of the carbene center are reported. The study should facilitate the discovery of even more active catalyst systems based on the unique BIAN‐NHC scaffold.