Catalyst-controlled divergence in cycloisomerisation reactions of N-propargyl-N-vinyl sulfonamides: gold-catalysed synthesis of 2-sulfonylmethyl pyrroles and dihydropyridines
Base-mediated 1,3-dipolar cycloaddition of pyridinium bromides with bromoallyl sulfones: a facile access to indolizine scaffolds
作者:Chetna Jadala、Velma Ganga Reddy、Namballa Hari Krishna、Nagula Shankaraiah、Ahmed Kamal
DOI:10.1039/d0ob01696a
日期:——
synthetic strategy has been developed for the construction of substituted indolizines from a unique combination of pyridiniumsalts and 2-bromoallyl sulfones. This approach does not compromise with the diverse substitutions on both the pyridiniumsalts and 2-bromoallyl sulfones. Wide substrate scope, operational simplicity, milder reaction conditions and good to moderate yields are the merits associated with
Twofold Radical-Based Synthesis of <i>N</i>,<i>C</i>-Difunctionalized Bicyclo[1.1.1]pentanes
作者:Helena D. Pickford、Jeremy Nugent、Benjamin Owen、James. J. Mousseau、Russell C. Smith、Edward A. Anderson
DOI:10.1021/jacs.1c04180
日期:2021.7.7
Bicyclo[1.1.1]pentylamines (BCPAs) are of growing importance to the pharmaceutical industry as sp3-rich bioisosteres of anilines and N-tert-butyl groups. Here we report a facile synthesis of 1,3-disubstituted BCPAs using a twofold radical functionalization strategy. Sulfonamidyl radicals, generated through fragmentation of α-iodoaziridines, undergo initial addition to [1.1.1]propellane to afford iodo-BCPAs;
which otherwise are essentially reluctant towards F‐nucleoplilic addition, now readily participate in this fluoroallylation reaction. Furthermore, this strategy provides an elegant example for the generation, as well as functionalization, of α‐CF3‐substituted benzylic radical intermediates using cheap and readily available starting materials.
A cascade process for the synthesis of <i>ortho</i>-formyl allyl aryl ethers and 2<i>H</i>-chromen-2-ol derivatives from arynes <i>via</i> trapping of <i>o</i>-quinone methide with an activated alkene
作者:Abhilash Sharma、Pranjal Gogoi
DOI:10.1039/c8ob02507j
日期:——
A transition-metal free synthetic strategy has been developed for the direct synthesis of ortho-formyl substituted allyl aryl ethers via a cascade three-component coupling of arynes, activated alkene and N,N-dimethylformamide. The reaction proceeds via C–O and C–Cbond cleavage as well as C–C and two new C–Obond formations in a single reaction vessel. The methodology provides a good yield of ortho-formyl
Direct synthesis of <i>ortho</i>-methylthio allyl and vinyl ethers <i>via</i> three component reaction of aryne, activated alkene and DMSO
作者:Hemanta Hazarika、Pranjal Gogoi
DOI:10.1039/d0ob00275e
日期:——
A synthetic strategy has been developed for the direct synthesis of ortho-methylthio allyl and vinyl ethers via three-component reaction of in situ generated aryne, activated alkene and DMSO. This reaction proceeds via several bond cleavage and bond formation processes in a single operation. Mechanistic studies reveal that DMSO served as both a methylthiolating agent and an oxygen source. This synthetic