Catalytic Electrochemical C–H Iodination and One-Pot Arylation by ON/OFF Switching of Electric Current
摘要:
Palladium-catalyzed electrochemical iodination and one-pot arylation of arylpyridines are described. Ortho-selective C-H iodination proceeded via dual activation of each substrate by a palladium catalyst and an electrode. Various aryl groups were introduced at the ortho positions of arylpyridines by ON/OFF switching of two different catalytic cycles using the same palladium catalyst in a one-pot fashion.
Ambient temperatureruthenium‐catalyzedC−H arylations were accomplished by visiblelight without additional photocatalysts. The robustness of the ruthenium‐catalyzedC−H functionalization protocol was reflected by a broad range of sensitive functional groups and synthetically useful pyrazoles, triazoles and sensitive nucleosides and nucleotides, as well as multifold C−H functionalizations. Biscyclometalated
Decarboxylative Acylation of Arenes with α-Oxocarboxylic Acids via Palladium-Catalyzed C−H Activation
作者:Mingzong Li、Haibo Ge
DOI:10.1021/ol1012857
日期:2010.8.6
An efficient palladium-catalyzeddecarboxylative acylation of unactivated arenes with α-oxocarboxylic acids is reported. This method provides a novel access to aryl ketones.
报道了未活化的芳烃与α-氧代羧酸的有效的钯催化的脱羧酰化。该方法为芳基酮提供了一种新颖的途径。
Ruthenium-catalyzed C–H allylation of arenes with allylic amines
作者:Rui Yan、Zhong-Xia Wang
DOI:10.1039/c8ob00723c
日期:——
Ru-catalyzed pyridyl-directed C–H allylation of arenes with allylicamines has been developed. This reaction was carried out in the presence of 5 mol% of [Ru(p-cymene)Cl2]2 and 0.5 equiv. of AgOAc in CF3CH2OH at 75 °C, affording the allylated products of arenes in moderate to excellent yields. The method exhibits a wide scope of allylicamines and arenes and shows a good compatibility of functional groups
elimination. Two types of catalytically relevant species were identified, and the reactivities of these species, combined with the results of the kinetic studies, suggest that the rate-limiting step is the exchange of the COD ligand with the alkenyl ester. On the basis of the elucidated mechanism, the first catalytic coupling reaction using aromatic C–H bonds with C–O bonds of ethers was also developed
A catalytic variant of the directthiolation of arenes, bearing directing groups, with disulfides or thiols has been developed under palladium and copper co‐catalysis. Both sulfenyl moieties of the disulfide could be incorporated into the thiolated products, therefore, the reactions reached completion with only half an equivalent of disulfide, with respect to the starting arene. Experimental evidence
在钯和铜的共催化下,开发了带有二价硫或硫醇的带有导向基团的芳烃直接硫醇化的催化变体。二硫化物的两个亚硫基部分都可以结合到硫醇化产物中,因此,相对于起始芳烃,仅用一半当量的二硫化物就可以完成反应。实验证据表明该反应是通过Pd II / Pd IV机制进行的。