Chelation-Assisted Rhodium-Catalyzed Direct Amidation with Amidobenziodoxolones: C(sp<sup>2</sup>)–H, C(sp<sup>3</sup>)–H, and Late-Stage Functionalizations
作者:Xu-Hong Hu、Xiao-Fei Yang、Teck-Peng Loh
DOI:10.1021/acscatal.6b02015
日期:2016.9.2
Air-stable and convenient amidobenziodoxolones as an amidating reagent were disclosed to enable direct amidation on a wide range of C(sp2)–H bonds of (hetero)arenes and alkenes, as well as unactivated C(sp3)–H bonds under RhIII catalysis. The approach to access 49 examples of structurally diverse amides is featured by mild conditions, complete chemoselectivity and regioselectivity, broad substrate scope
Cobalt-Catalyzed Directed Alkylation of Olefinic C–H Bond with Primary and Secondary Alkyl Chlorides
作者:Naohiko Yoshikai、Takeshi Yamakawa、Yuan Seto
DOI:10.1055/s-0034-1379247
日期:——
A cobalt–N-heterocyclic carbene catalytic system promotes pyridine-directed olefinic C–H alkylation reactions using a variety of primary and secondary alkyl chlorides under mild conditions. Radical clock experiments suggest that the reaction involves single-electron transfer from the cobalt intermediate to the alkyl chloride.
A [Cp*RhIII]‐catalyzed direct C−H amidation is carried out in ionic liquid. Both C(sp2)−H bonds of (hetero)arenes and alkenes and unactivated C(sp3)−H bonds can be easily amidated with high functional‐group tolerance and excellent yields under these conditions. Notably, using [Cp*RhIII]/[BMIM]BF4 (BMIM=1‐butyl‐3‐methylimidazolium) as the green and recyclable medium is environmentally benign, in light
[Cp * Rh III ]催化的直接CHH酰胺化反应在离子液体中进行。在这些条件下,(杂)芳烃和烯烃的C(sp 2)-H键和未活化的C(sp 3)-H键都容易被酰胺化,具有很高的官能团耐受性和优异的收率。值得注意的是,考虑到诸如昂贵的铑催化剂的可重复使用性等特性,使用[Cp * Rh III ] / [BMIM] BF 4(BMIM = 1-丁基-3-甲基咪唑鎓)作为绿色且可回收的介质对环境无害。避免剧毒的有机溶剂,温和的反应条件以及较短的反应时间。
Lewis Acid/Brønsted Acid Controlled Pd(II)-Catalyzed Chemodivergent Functionalization of C(<i>sp</i><sup>2</sup>)–H Bonds with <i>N</i>-(Arylthio)i(a)mides
作者:Manthena Chaitanya、Pazhamalai Anbarasan
DOI:10.1021/acs.orglett.8b01281
日期:2018.6.1
C–H bonds have been accomplished employing N-(arylthio)imides in combination with either Brønsted acid or Lewis acid, respectively. Notable features of the developed methodologies include excellent diversity, high functional group tolerance, wide substrate scope, and use of a single N–S reagent. Importantly, the developed hypothesis was also successfully extended to the amidation of C–H bonds. A plausible