A photochemical C–N coupling of aryl halides with nitroarenes is demonstrated for the first time. Catalyzed by a NiII complex in the absence of any external photosensitizer, readily available nitroarenes undergo coupling with a variety of aryl halides, providing a step‐economic extension to the widely used Buchwald–Hartwig C–N couplingreaction. The method tolerates coupling partners with steric‐congestion
首次证明了芳基卤化物与硝基芳烃的光化学C–N偶联。在没有任何外部光敏剂的情况下,通过Ni II络合物的催化,易得的硝基芳烃与各种芳基卤化物偶合,为广泛使用的Buchwald-Hartwig C-N偶合反应提供了经济上的扩展。该方法耐受具有对碱基和亲核试剂敏感的空间拥塞和官能团的偶联伴侣。机理研究表明,该反应是通过将由Ni I / Ni III循环生成的芳基加至亚硝基芳烃中间体而进行的。
Nickel-Catalyzed Amination of Aryl Tosylates
作者:Cai-Yan Gao、Lian-Ming Yang
DOI:10.1021/jo7022558
日期:2008.2.1
The cross-coupling of aryl tosylates with amines and anilines was accomplished by using a Ni-based catalyst system from the combination of Ni(II)−(σ-aryl) complexes/N-heterocyclic carbenes (NHCs). The feature, scope, and limitation of this reaction are disclosed.
Arylation of both acyclic ketones and primary and secondary amines was achieved using a new, simple, stable, and easy-to-access nickel(II)−halide complex bearing mixed PPh3/N-heterocyclic carbene ligands as a catalyst precursor. Acyclic ketones were first arylated at the α-position with the nickel catalyst. On the other hand, less basic amines, such as diphenylamine and 4-aminobenzophenone, were more
methoxy(hetero)arenes with amine nucleophiles such as aniline, indoline, and aminopyridine derivatives. This catalytic reaction is effective for the transformation of electron-deficient methoxyarenes possessing diverse functionalities (carbonyl, cyano, nitro, and halogen) as well as methoxyheteroarenes, including pyrazine, quinoline, isoquinoline, and pyridine derivatives. Intramolecular reactions provide six- and
Palladium-Catalyzed Aminations in Flow ... <i>on Water</i>
作者:Madison J. Wong、Erfan Oftadeh、John M. Saunders、Alex B. Wood、Bruce H. Lipshutz
DOI:10.1021/acscatal.3c05257
日期:2024.2.2
Aminations can be efficiently run, under plug flow conditions on water, catalyzed by low levels of a recyclable palladium precatalyst. General protocols to couple amines, both aryl and aliphatic, with aryl/heteroaryl bromides have been developed. Further highlights include “on water” conditions, short reaction times, recycling of the reaction medium, low levels of residual Pd in the isolated products
在低含量的可回收钯预催化剂的催化下,胺化反应可以在水的活塞流条件下高效进行。已经开发出将芳基胺和脂肪族胺与芳基/杂芳基溴化物偶联的通用方案。进一步的亮点包括“水上”条件、短反应时间、反应介质的回收利用、分离产物中残留 Pd 含量低以及作为绿色指标的低 E 因子,所有这些特征都展示了这种胺化反应通常运行的替代方案在批处理模式下。