Cobalt‐catalyzed C−H amination of arenes with alkylamines by the assistance of 8‐aminoquinoline as auxiliary through sp2 C−H bond functionalization has been achieved. Attractive features of this protocol include the low loading of the cobalt catalyst and the readily available reagents.
Nickel-catalyzed directed sulfenylation of sp<sup>2</sup> and sp<sup>3</sup> C–H bonds
作者:Xiaohan Ye、Jeffrey L. Petersen、Xiaodong Shi
DOI:10.1039/c5cc01970b
日期:——
Directed sulfenylation of both sp2 and sp3 C–H bonds was achieved through nickel catalyzed directed C–S bond formation, giving the desired product in good to excellent yield (up to 90%).
for the carbonylation industry. Transition-metal-catalyzed oxidative C–H/C(X)–H carbonylation with CO provides one of the most straightforward approaches to construct carbonyl compounds. However, the use of stoichiometric oxidants would bring several drawbacks such as high cost and undesired chemical waste. Especially, the explosion limit is a potential safety hazard in oxidative carbonylation using
一氧化碳是羰基化行业中一种丰富且具有成本效益的C1构建基块。过渡金属催化的CO氧化C–H / C(X)–H羰基化反应是最简单的羰基化合物构建方法之一。然而,使用化学计量的氧化剂将带来一些缺点,例如高成本和不希望的化学废物。特别是,爆炸极限是在使用O 2作为氧化剂进行氧化羰基化反应中的潜在安全隐患。为克服这些问题,已经设计了一种利用阳极氧化来循环钴催化剂和H 2的氧化C–H / N–H羰基化的电化学方法。在阴极产生。分子内和分子间羰基化产物可以以良好的官能团耐受性获得,产率为31%–99%。通过XANES和CV的研究提出了一种可能的反应机理,该反应机理涉及Co II / Co III / Co I催化循环。
An Approach to Five-Membered Lactams from Aliphatic Amides and Terminal Acetylenes by Nickel Catalysis
diverse five‐membered lactams from aliphaticamides and terminal acetylenes with the assistance of an 8‐aminoquinolyl auxiliary has been achieved. A broad range of terminal acetylenes and aliphaticamides proved to be the efficient coupling partners, furnishing the corresponding lactams in moderate to good yields. The transformation is proven to undergo an oxidative alkynylation followed by the intramolecular
Copper-Catalyzed C–H Carbamoyloxylation of Aryl Carboxamides with CO<sub>2</sub> and Amines at Ambient Conditions
作者:Xiang Luo、Xianheng Song、Wenfang Xiong、Jianheng Li、Mingkang Li、Zefeng Zhu、Shuxian Wei、Albert S. C. Chan、Yong Zou
DOI:10.1021/acs.orglett.9b00122
日期:2019.4.5
A copper-catalyzed, 8-aminoquinoline-assisted, one-potthree-component coupling of aryl carboxamides, CO2, and amines has been developed. This protocol proceeds smoothly in the presence of inexpensive CuI and MnO2 at room temperature under atmospheric CO2 pressure, leading to simultaneous construction of C–O and C–N bonds. The reaction displays a broad substrate scope, high functional group tolerance