Visible Light-Promoted Aliphatic C–H Arylation Using Selectfluor as a Hydrogen Atom Transfer Reagent
作者:Hong Zhao、Jian Jin
DOI:10.1021/acs.orglett.9b01635
日期:2019.8.16
A mild, practical method for direct arylation of unactivated C(sp3)–H bonds with heteroarenes has been achieved via photochemistry. Selectfluor is used as a hydrogen atom transfer reagent under visible light irradiation. A diverse range of chemical feedstocks, such as alkanes, ketones, esters, and ethers, and complex molecules readily undergo intermolecular C(sp3)–C(sp2) bond formation. Moreover, a
protocol for direct C–H alkylation and acylation of N-heterocycles, using readily accessible carboxylic acids as radical precursors under visible-light irradiation without a photocatalyst and an additional acid additive, has been developed. This protocol provides expedient access to substituted N-heterocycles under mild and metal-free conditions. Mechanistic experiments indicate that this reaction proceeds
Surgical Cleavage of Unstrained C(
<i>sp</i>
<sup>3</sup>
)−C(
<i>sp</i>
<sup>3</sup>
) Bonds in General Alcohols for Heteroaryl C−H Alkylation and Acylation
作者:Yaxin Wang、Le Yang、Shuai Liu、Lixia Huang、Zhong‐Quan Liu
DOI:10.1002/adsc.201900975
日期:2019.10.8
We reported herein a predictable and surgicalcleavage of carbon‐carbon bond in alcohols. A wide range of 1°, 2° and 3° alcohols including sugars and steroids without ring strain or steric hindrance were all compatible with this system. Also it offered a green and practical strategy for generation of alkyl/acyl radicals using alcohols as the sources. Besides, the features of visible‐light‐initiation