found to be a highly efficient promoter system for the intra- and intermolecular hydroamidation of unactivated alkenes. Unlike other methods, a vast array of functional groups is tolerated at the nitrogen and alkene moieties. The reaction produces the corresponding nitrogen-containing compounds in excellent yields and good diastereoselectivities. The use of HFIP as solvent proved crucial for the proper
Anchimeric Assistance in Hydrogen-Atom Transfer to Bromine
作者:Anna K. Croft、Christopher J. Easton
DOI:10.1071/ch04058
日期:——
N-bromosuccinimide exhibit anchimeric assistance by neighbouring ester and amido groups. Rate enhancement occurs through electron donation to the electropositive carbon centre that develops in the transition state of the hydrogen-atom transfer to bromine. The extent of the effect depends on the electron demand at the benzylic position and the electron-donating ability of the neighbouring group.
Visible light bromide catalysis for oxazoline, pyrrolidine, and dihydrooxazine syntheses <i>via</i> C<sub>sp<sup>3</sup></sub>–H functionalizations
作者:Navdeep Kaur、Elizabeth C. Ziegelmeyer、Olutayo N. Farinde、Jonathon T. Truong、Michelle M. Huynh、Wei Li
DOI:10.1039/d1cc04588a
日期:——
(N)-centered radical for a site-selective hydrogenatomtransfer (HAT) process. This strategy enabled the unconventional syntheses of a number of N-heterocycles dependent on the amide identity. We also discovered a nucleophilicity-dependent kinetic resolution for stereochemical differentiation of Csp3–H bonds that enabled the stereoselective synthesis of cis- and trans-oxazolines.
此处描述了催化苄基 C sp 3 –H 功能化协议。这种可见光介导的过程集中在利用溴化物催化剂和氧化剂来生成以氮 (N) 为中心的自由基,用于位点选择性氢原子转移 (HAT) 过程。这种策略使依赖酰胺身份的许多 N-杂环的非常规合成成为可能。我们还发现了 C sp 3 -H 键立体化学分化的亲核依赖性动力学分辨率,这使得顺式和反式恶唑啉的立体选择性合成成为可能。
Selective and Catalytic Arylation of <i>N</i>-Phenylpyrrolidine: sp<sup>3</sup> C−H Bond Functionalization in the Absence of a Directing Group
作者:Bengü Sezen、Dalibor Sames
DOI:10.1021/ja050269o
日期:2005.4.1
We herein describe our studies on arylation of N-phenylpyrrolidine, which led to the development of a new transformation for the direct and selective arylation of sp3 C-H bonds in the absence of a directing group. In this method, Ru(H)2(CO)(PCy3)3 4 was used as the catalyst, and preliminary mechanistic studies suggested that Ru(Ph)(I)(CO)(PCy3)2 5 is the key intermediate of the catalytic cycle. A large
Remote Radical Desaturation of Unactivated C−H Bonds in Amides
作者:Yong Xia、Kalipada Jana、Armido Studer
DOI:10.1002/chem.202103509
日期:2021.12
A copper-catalyzed/silver-promoted desaturation method is described which allows the regioselective conversion of various unactivated N-alkylamides at remote sites to the corresponding N-alkenylamides via N-centred radical mediated 1,5 hydrogen atom transfer, metal-mediated oxidation and deprotonation. The transformation shows good functional group tolerance and can be used for late-stage desaturation
描述了铜催化/银促进的去饱和方法,该方法允许通过以 N 为中心的自由基介导的 1,5 氢原子转移、金属介导的氧化和去质子化。该转化表现出良好的官能团耐受性,可用于药物衍生物和生物学上更相关的化合物的后期去饱和。