Tosyloxybenziodoxolone: A Platform for Performing the Umpolung of Alkynes in One-Pot Transformations
作者:Julien Borrel、Jerome Waser
DOI:10.1021/acs.orglett.1c03771
日期:2022.1.14
Ethynylbenziodoxolones (EBXs) are commonly encountered reagents for the electrophilic alkynylation of nucleophiles. Herein, we report a one-pot, two-step process for EBX generation and their direct application in substrate functionalization. Our approach enables us to bypass the originally mandatory isolation and purification of the reagents, resulting in a more efficient synthesis. We could apply
Practical and Highly Selective CH Functionalization of Structurally Diverse Ethers
作者:Miao Wan、Zhilin Meng、Hongxiang Lou、Lei Liu
DOI:10.1002/anie.201407083
日期:2014.12.8
A trityl ion mediated CHfunctionalization of ethers with a wide range of nucleophiles at ambient temperature has been developed. The reaction displays high chemoselectivity and good functional group tolerance. The protocol also exhibits excellent regio‐ and diastereoselectivities for the unsymmetric ethers, thus stereoselectively generating highlyfunctionalized disubstituted 2,5‐trans tetrahydrofurans
A Mild and Regiospecific Synthesis of Pyrazoleboranes
作者:Andrew W. Brown、Júlia Comas-Barceló、Joseph P. A. Harrity
DOI:10.1002/chem.201701019
日期:2017.4.19
Alkynylboranes show unprecedented reactivity in their [4+2] cycloaddition of sydnones offering access to fully substituted pyrazoles within a few hours at room temperature. This method delivers synthetically valuable pyrazoleboranes with complete control of regioselectivity, and these intermediates can be further elaborated through functionalization of the C−B bond.
Direct oxidative C–H alkynylation of <i>N</i>-carbamoyl tetrahydroisoquinolines and dihydroisoquinolines
作者:Lei Chen、Chuanxi Sun、Guidong Feng、Min Cao、Shu-lei Zhao、Jun Yan、Ren-zhong Wan、Lei Liu
DOI:10.1039/c8ob00373d
日期:——
An efficient oxidative C–H alkynylation of N-carbamoyl tetrahydroisoquinolines mediated by a TEMPO oxoammonium salt has been established. A variety of electronically varied N-carbamoyl tetrahydroisoquinolines reacted with a range of alkynyl potassium trifluoroborates smoothly under mild metal-free conditions. Dihydroisoquinolines were also suitable components for the reaction. The synthetic applicability