A method for five- and six-membered heterocycle formation by palladium-catalyzed C-H/N-H coupling is presented. The method employs a picolinamide directing group, PhI(OAc)(2) oxidant, and toluene solvent at 80-120 degrees C. Cyclization is effective for sp(2) as well as aliphatic and benzylic sp(3) C-H bonds.
A method for five- and six-membered heterocycle formation by palladium-catalyzed C-H/N-H coupling is presented. The method employs a picolinamide directing group, PhI(OAc)(2) oxidant, and toluene solvent at 80-120 degrees C. Cyclization is effective for sp(2) as well as aliphatic and benzylic sp(3) C-H bonds.
Rh<sup>I</sup>/Rh<sup>III</sup> catalyst-controlled divergent aryl/heteroaryl C–H bond functionalization of picolinamides with alkynes
作者:Ángel Manu Martínez、Javier Echavarren、Inés Alonso、Nuria Rodríguez、Ramón Gómez Arrayás、Juan C. Carretero
DOI:10.1039/c5sc01885d
日期:——
Switchable site-selectivity through catalyst control is achieved in the direct functionalization of picolinamides that contain two distinct C–H sites to construct diverse scaffolds from the same starting material.
Palladium-catalyzed ortho-C–H olefination of phenylalanine and phenylethylamine derivatives assisted by a removable picolinamide group has been achieved. This protocol shows broad substrate scope, functional tolerance and moderate to high yields, thus affording a practical approach for the direct modification of phenylalanine and phenylethylamine derivatives.
Palladium‐Catalyzed Remote
<i>δ</i>
‐C−H Selenylation of Arylethylamide and Alkenylethylamide Derivatives
作者:Wenbo Ma、Yunhao Zhou、Yang Wang、Bo Li、Tao Zheng、Zemin Cheng、Ruhuai Mei
DOI:10.1002/adsc.202200691
日期:2022.10.18
A palladium-catalyzed remote δ-C−H selenylation of arylethylamidederivatives with readily available diselenides has been reported. This protocol relies on the use of a removable picolinamide directing group to access unsymmetrical diaryl selenides in 45–98% yields. Furthermore, the inactivated δ-C(alkenyl)−H bond was also compatible in this reaction and afforded the thermo-dynamically unfavorable