Mild oxidation of bromides by iodine(III) reagents generated active electrophilic bromination species that were reacted with polyprenoids. By simple and minor variations of an I(III)/Br combination, the reactivity could be selectively steered toward dibromination, oxybromination, or bromocyclization, giving access to a wide array of brominated motifs.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1021/acs.orglett.7b02125 | DOI Listing |
Nat Chem
June 2024
Department of Chemistry, Northeast Normal University, Changchun, China.
Building molecular complexity from simple feedstocks through precise peripheral and skeletal modifications is central to modern organic synthesis. Nevertheless, a controllable strategy through which both the core skeleton and the periphery of an aromatic heterocycle can be modified with a common substrate remains elusive, despite its potential to maximize structural diversity and applications. Here we report a carbene-initiated chemodivergent molecular editing of indoles that allows both skeletal and peripheral editing by trapping an electrophilic fluoroalkyl carbene generated in situ from fluoroalkyl N-triftosylhydrazones.
View Article and Find Full Text PDFCommun Chem
June 2021
Guangzhou Municipal and Guangdong Provincial Key Laboratory of Protein Modification and Degradation & Molecular Target and Clinical Pharmacology, State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences & the Fifth Affiliated Hospital, Guangzhou Medical University, Guangzhou, Guangdong, China.
Ortho-functionalized phenols and their derivatives represent prominent structural motifs and building blocks in medicinal and synthetic chemistry. While numerous synthetic approaches exist, the development of atom-/step-economic and practical methods for the chemodivergent assembly of diverse ortho-functionalized phenols based on fixed catalyst/substrates remains challenging. Here, by selectively controlling the reactivities of different sites in methylenecyclopropane core, Rh(III)-catalyzed redox-neutral and tunable C-H functionalizations of N-phenoxyacetamides are realized, providing access to both ortho-functionalized phenols bearing linear dienyl, cyclopropyl or allyl ether groups, and cyclic 3-ethylidene 2,3-dihydrobenzofuran frameworks under mild cross-coupling conditions.
View Article and Find Full Text PDFOrg Lett
June 2021
National Institute of Pharmaceutical Education and Research (NIPER), Hyderabad 500 037, Telangana India.
Herein, we report an acid-controlled highly tunable selectivity of Rh(III)-catalyzed [4 + 2] and [3 + 3] annulations of -carboxamide indoles with iodonium ylides lead to form synthetically important tricyclic and tetracyclic -heterocycles. Here, iodonium ylide serves as a carbene precursor. The protocol proceeds under operationally simple conditions and provides novel tricyclic and tetracyclic scaffolds such as 3,4-dihydroindolo[1,2-]quinazoline-1,6(2,5)-dione and 1-[1,3]oxazino[3,4-]indol-1-one derivatives with a broad range of functional group tolerance and moderate to excellent yields.
View Article and Find Full Text PDFOrg Lett
December 2020
The Fifth Affiliated Hospital, Key Laboratory of Molecular Target & Clinical Pharmacology and the State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences, Guangzhou Medical University, Guangzhou, Guangdong 511436, China.
An unprecedented Rh(III)-catalyzed cascade C-H activation/Lossen rearrangement of aromatic amides with methyleneoxetanones has been realized along with a tunable C-N bond reductive elimination/trans esterification, giving divergent access to quinolinones and dihydroisoquinolinones via selective ring-opening of the four-membered lactone unit. Combined computational and experimental mechanistic studies defined the solvent-involved distinguished reaction paths, the origin of the observed chemodivergence, as well as the role of the substituent attached at the oxidizing directing group in tuning the reaction outcomes.
View Article and Find Full Text PDFOrg Lett
June 2019
Key Laboratory of Molecular Target & Clinical Pharmacology and State Key Laboratory of Respiratory Disease, School of Pharmaceutical Sciences & the Fifth Affiliated Hospital , Guangzhou Medical University, Guangzhou , Guangdong 511436 , China.
The efficient couplings of diverse N-arylureas and methyleneoxetanones have been realized via Rh(III)-catalyzed and solvent-controlled chemoselective C-H functionalization, which involved the tunable β-H elimination and β-O elimination processes, thereby giving divergent access to quinolin-2(1 H)-ones and ortho-allylated N-arylureas with broad substrate compatibility and good functional group tolerance. the divergent synthetic utilities of the transformations have also been exemplified by subsequently tandem C-H allylation, unsymmetrical C-H functionalization, alternative reaction mode, as well as removal of the carbamoyl group.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!