transition metal free, highly efficient, sulfenylation of ketene dithioacetals catalyzed by an HBr–DMSO system is achieved. This strategy employs inexpensive and readily available HBr and DMSO to provide a direct C–H bond sulfenylation with a broad range of aryl thiols. Highlights of the present strategy are convenient, straightforward approach, metal free, short reaction time and excellent yields. This
Iron-catalyzed alkylation of α-oxo ketene dithioacetals
作者:Qin Yang、Ping Wu、Jiping Chen、Zhengkun Yu
DOI:10.1039/c4cc02264e
日期:——
Iron-catalyzed alkylation of α-oxo ketene dithioacetals by styrenes efficiently afforded highly functionalized tetrasubstituted olefins.
铁催化的α-氧酮二硫代醛与苯乙烯的烷基化反应高效地合成了高度官能化的四取代烯烃。
Alternative Palladium-Catalyzed Vinylic C−H Difluoroalkylation of Ketene Dithioacetals Using Bromodifluoroacetate Derivatives
作者:Shuangquan Tian、Xiaoning Song、Dongsheng Zhu、Mang Wang
DOI:10.1002/adsc.201701554
日期:2018.4.3
A palladium‐catalyzedcross‐coupling of α‐oxo ketene dithioacetals and bromodifluoroacetate derivatives has been developed for the synthesis of a class of CF2‐containing tetra‐substituted olefins, which has potential to extend to drug design and material application. The process is proposed to involve two single electron transfer processes accompanied by an alternative loop from palladium(0) to palladium(I)
Ruthenium- and Rhodium-Catalyzed Chemodivergent Couplings of Ketene Dithioacetals and α-Diazo Ketones via C–H Activation/Functionalization
作者:Manman Wang、Lingheng Kong、Qiyue Wu、Xingwei Li
DOI:10.1021/acs.orglett.8b01890
日期:2018.8.3
Chemodivergent coupling of α-acylketene dithioacetals with diazo compounds has been realized under catalyst control. The Ru(II)-catalyzed C–H activation occurred at the olefinic position, and 1:2 coupling with α-diazoketoesters leads to furfurylation. In contrast, the Rh(III)-catalyzed C–H functionalization occurred at both the olefinic and the ortho C(aryl)–H positions, and [4 + 2] annulation afforded
This work describes an electrochemicalammoniumcation enabled hydropyridylation of ketone-activated alkenes under metal- and exogenous reductant free conditions giving access to β-pyridyl ketones, through dual proton-coupled electron transfer and radical cross-coupling. It features a broad substrate scope and allows a gram-scale synthesis. Ammonium chloride plays various roles in this transformation