A metal-free protocol of direct C(sp3)–H cyanation with cyanobenziodoxolones functioning as both cyanating reagents and oxidants was developed. Unactivated substrates, such as alkanes, ethers and tertiary amines, were thereby transformed to the corresponding nitriles in moderate to high yields. Mechanistic studies indicated that the cyanation proceeded with two potential pathways, which is highly dependent
effective direct hydrogen‐atom transfer catalyst for C−H activation. Using the alkylation of C−Hbonds with electron‐deficient alkenes as a model study revealed an extremely broad substrate scope, enabling easy access to a variety of important synthons. This eosin Y‐based photocatalytic hydrogen‐atom transfer strategy is promising for diverse functionalization of a wide range of native C−Hbonds in a green
reacts with tosyl cyanide to afford the corresponding nitrile in a highly efficient manner. The present methodology is widely applicable to various starting materials including ethers, alcohols, amine derivatives, alkanes, and alkylbenzenes. This newly developed C–H cyanation protocol provides a powerful tool for selective one-carbon elongation for the construction of architecturally complex molecules
Direct C(sp<sup>3</sup>)–H Cyanation Enabled by a Highly Active Decatungstate Photocatalyst
作者:Kunsoon Kim、Seulchan Lee、Soon Hyeok Hong
DOI:10.1021/acs.orglett.1c01846
日期:2021.7.16
Photochemically Induced Radical Transformation of C(sp<sup>3</sup>)–H Bonds to C(sp<sup>3</sup>)–CN Bonds
作者:Shin Kamijo、Tamaki Hoshikawa、Masayuki Inoue
DOI:10.1021/ol202659e
日期:2011.11.4
A general protocol for direct transformation of unreactive C(sp(3))-H bonds to C(sp(3))-CN bonds has been developed. The C-H activation was effected by photoexcited benzophenone, and the generated carbon radical was subsequently trapped with tosyl cyanide to afford the corresponding nitrile in a highly efficient manner. The present methodology Is widely applicable to versatile starting materials and, thus, serves as a powerful tool for selective one-carbon elongation for construction of architecturally complex molecules.