degrees C under an aerobicconditions smoothly undergoes homo-coupling to give the corresponding symmetrical 1,3-butadiynes in 70-99% yields. In addition, (arylethynyl)trimethylsilanes are found to couple with aryl triflates and chlorides in the presence of Cu(I)/Pd(0) (10 mol %/5 or 10 mol %) cocatalyst system to give the corresponding diarylethynes in 49-99% yields. The cross-coupling reaction is
Electrochemical nickel-catalyzed cross-coupling of glycosyl thiols with preactivated phenols and ketones
作者:Fuxin Li、Hui Liu、Wanyu Xing、Qingju Zhang、Liming Wang
DOI:10.1039/d4ob00442f
日期:——
An efficient electrochemical nickel-catalyzed cross-coupling reaction has been reported here for the synthesis of S-glycosides from preactivated phenols and ketones under mild conditions. Various glycosyl thiols, including unprotected sugar, and a diverse range of aryl/alkenyl triflates, including some complex biorelevant phenols and ketones, were well tolerated in this method.
We report a remote arylation in less than 10 min reaction time at room temperature over a distance of up to 11 carbons. The unprecedentedspeed is enabled by the air-stable PdI dimer [Pd(μ-I)(PCy2tBu)]2.
Room Temperature Carbonylation of (Hetero) Aryl Pentafluorobenzenesulfonates and Triflates using Palladium-Cobalt Bimetallic Catalyst: Dual Role of Cobalt Carbonyl
作者:Jayan T. Joseph、Ayyiliath M. Sajith、Revanna C. Ningegowda、Sheena Shashikanth
DOI:10.1002/adsc.201600736
日期:2017.2.2
method for the carbonylation of (hetero) aryl pentafluorobenzenesulfonates and triflates under exceptionally mild conditions using palladium/dicobalt octacarbonyl [Pd/Co2(CO)8] has been developed. Besides acting as carbon monoxide (CO) source, Co2(CO)8 enhances the reaction rate by accelerating the CO insertion through an in situ generated bimetallic palladium cobalt tetracarbonyl [Pd‐Co(CO)4] complex
已经开发了一种在异常温和的条件下使用钯/二钴八羰基[Pd / Co 2(CO)8 ]对(杂)芳基五氟苯磺酸盐和三氟甲磺酸酯进行羰基化的有效方法。除了充当一氧化碳(CO)源外,Co 2(CO)8还可以通过原位生成的双金属钯四羰基钴[Pd-Co(CO)4)加速CO的插入,从而提高反应速率。] 复杂的。在优化的反应条件下,各种活化和失活的,以及位阻和杂芳族底物的羰基化反应在室温下均能有效进行。生物学上相关的异古瓦汀和拉扎贝米中间体的高化学选择性和改进的合成方法突出了其作为有价值的合成方法的范围。该协议的通用性进一步扩展到其他亲电试剂(溴化物,氯化物和甲苯磺酸盐)。