Manganese-Catalyzed Direct Nucleophilic C(sp<sup>2</sup>)H Addition to Aldehydes and Nitriles
作者:Bingwei Zhou、Yuanyuan Hu、Congyang Wang
DOI:10.1002/anie.201506187
日期:2015.11.9
Herein, a manganese‐catalyzed nucleophilicaddition of inert C(sp2)H bonds to aldehydes and nitriles is disclosed by virtue of a dual activation strategy. The reactions feature mild reaction conditions, excellent regio‐ and stereoselectivity, and a wide substrate scope, which includes both aromatic and olefinic CH bonds, as well as a large variety of aldehydes and nitriles. Moreover, mechanistic studies
Isolation of Cp*Co<sup>III</sup>
-Alkenyl Intermediate in Efficient Cobalt-Catalyzed C−H Alkenylation with Alkynes
作者:Malay Sen、Nimmakuri Rajesh、Balakumar Emayavaramban、J. Richard Premkumar、Basker Sundararaju
DOI:10.1002/chem.201705183
日期:2018.1.9
A general and efficient procedure for C−H alkenylation of arenes with a broad substrate scope catalyzed by Cp*CoIII was demonstrated with alkynes. A highly selective mono‐alkenylation and sequential bis‐C−H bond functionalization was displayed to exemplify the versatility of the cobalt catalyst. Isolation of cationic Cp*CoIII–alkenyl intermediate was achieved under identical catalytic conditions to
用炔烃证明了由Cp * Co III催化的具有广泛底物范围的芳烃的CH链烯基化的通用有效方法。高选择性的单烯基化和顺序的双CH键功能化显示了钴催化剂的多功能性。在相同的催化条件下实现了阳离子Cp * Co III-烯基中间体的分离,以进一步建立拟议的途径。
Monodisperse CuPd alloy nanoparticles as efficient and reusable catalyst for the C (sp
<sup>2</sup>
)–H bond activation
activation of C–H bonds is very important for the construction of a variety of biologically active molecules. Supported alloy nanoparticles are of great interest in various catalytic applications due to the synergistic effects between different metals. Here, well-dispersed CuPd alloy nanoparticles supported on reduced grapheneoxide (rGO) were synthesized and found to be highlyefficient and recyclable
A simple and efficient method for Cp*CoIII-catalyzed C–H bond alkylation using activated olefins was developed. Selective C–H monoalkylation was performed at ambient temperature. One-pot symmetrical dialkylation and sequential unsymmetrical C–H dialkylation were performed to give the desired products in excellent yields. The reaction was found to proceed through an M–alkyl intermediate after migratory
开发了一种使用活化烯烃进行Cp * Co III催化的C–H键烷基化的简单有效的方法。选择性C–H单烷基化反应是在环境温度下进行的。一锅对称二烷基化和连续不对称CH二烷基化反应以优异的收率得到了所需的产物。发现该反应在迁移插入后通过M-烷基中间体进行,并且该中间体进行原金属脱金属反应,以产生预期的烷基化产物以及再生的催化剂。
Catalytic, Directed C–C Bond Functionalization of Styrenes
A method for catalytic conversion of C(aryl)-C(alkenyl) bonds in styrene derivatives to new C-C bonds is developed. In the presence of a rhodium catalyst, the alkenyl groups of styrenes bearing a pyrazolyl directing group were efficiently converted to other carbon substituents upon reacting with various alkenes including styrenes, aliphatic alkenes, and allyl alcohols. It is also indicated that the
开发了一种将苯乙烯衍生物中的 C(芳基)-C(烯基)键催化转化为新 CC 键的方法。在铑催化剂的存在下,带有吡唑基导向基团的苯乙烯的烯基在与包括苯乙烯、脂肪族烯烃和烯丙醇在内的各种烯烃反应时有效地转化为其他碳取代基。还表明CC键断裂是通过氢金属化/β-碳消除途径进行的。