185981-82-2Relevant academic research and scientific papers
Stepwise mechanism for the bromination of arenes by a hypervalent iodine reagent
Arrieta, Ana,Cossío, Fernando P.,Granados, Albert,Shafir, Alexandr,Vallribera, Adelina
, p. 2142 - 2150 (2020/03/11)
A mild, metal-free bromination method of arenes has been developed using the combination of bis(trifluoroacetoxy)iodobencene and trimethylsilyl bromide. In situ-formed dibromo(phenyl)-λ3-iodane (PhIBr2) is proposed as the reactive intermediate. This methodology using PIFA/TMSBr has been applied with success to a great number of substrates (25 examples). The treatment of mono-substituted activated arenes led to para-brominated products (2u-z) in excellent 83-96% yields. Density functional theory calculations indicate a stepwise mechanism involving a double bromine addition followed by a type II dyotropic reaction with concomitant re-aromatization of the six-membered ring.
Regioselective electrophilic aromatic bromination: Theoretical analysis and experimental verification
Li, Hui-Jing,Wu, Yan-Chao,Dai, Jian-Hong,Song, Yan,Cheng, Runjiao,Qiao, Yuanyuan
, p. 3401 - 3416 (2014/04/17)
Electrophilic aromatic bromination is the most common synthetic method used to prepare aryl bromides, which are very useful intermediates in organic synthesis. To understand the experimental results in electrophilic aromatic brominations, ab initio calculations are used here for a tentative analysis of the positional selectivity. The calculated results agree well with the corresponding experimental data, and the reliability of the resulting positional selectivity was verified by the corresponding experimental data.
Asymmetric [C + NC + CC] coupling entry to the naphthyridinomycin natural product family: Formal total synthesis of cyanocycline A and bioxalomycin β2
Garner, Philip,Kaniskan, H. Uemit,Keyari, Charles M.,Weerasinghe, Laksiri
experimental part, p. 5283 - 5294 (2011/08/05)
A full account of our [C + NC + CC] coupling approach to the naphthyridinomycin family of natural products is presented, culminating in formal total syntheses of cyanocycline A and bioxalomycin β2. The key complexity-building reaction in the synthesis involves the Ag I-catalyzed endo-selective [C + NC + CC] coupling of aldehyde 7, (S)-glycyl sultam 8, and methyl acrylate (9) to provide the highly functionalized pyrrolidine 6, which was carried forward to an advanced intermediate (compound 33) in Fukuyama's synthesis of cyanocycline A. Since cyanocycline A has been converted to bioxalomycin β2, this constitutes a formal synthesis of the latter natural product as well. The multicomponent reaction-based strategy reduces the number of steps previously needed to assemble these complex molecular targets by one-third. This work highlights the utility of the asymmetric [C + NC + CC] coupling reaction in the context of a complex pyrrolidine-containing target and provides an illustrative guide for its application to other synthesis problems. The synthesis also fueled collaborative biological and biochemical research that identified a unique small molecule inhibitor of cell migration (compound 30).
Asymmetrie total syntheses of (-)-renieramycin M and G and (-)-jorumycin using aziridine as a lynchpin
Wu, Yan-Chao,Zhu, Jieping
supporting information; experimental part, p. 5558 - 5561 (2010/02/28)
"Chemical Equation Presented" By exploring the triple reactivity of two aziridines and double nucleophilicity of two aromatics, convergent and versatile syntheses of the above four natural products were developed.
An efficient synthetic approach to cyanocycline A and bioxalomycin β2 via [C+NC+CC] coupling
Kaniskan, H. Uemit,Garner, Philip
, p. 15460 - 15461 (2008/09/19)
The AgI catalyzed [C+NC+CC] coupling reaction of a 2,3-bisaminoaldehyde 5, l-glycyl sultam 6, and methyl acrylate provides highly functionalized pyrrolidine 7, the key intermediate in an efficient synthetic approach to the cyanocycline and biox
Biaryl formation using the Suzuki protocol: Considerations of base, halide, and protecting group
Benbow, John W.,Martinez, Bonnie L.
, p. 8829 - 8832 (2007/10/03)
The generation of aryl anions prior to quenching with a trialkyl berate has been shown to be sensitive to the composition of the aryl substrate. Aryl iodides containing remote benzyl ether substituents undergo trans-metallation with sec-BuLi to cleanly give the desired aryl anions whereas the corresponding bromides afford appreciable quantities of dianionic intermediates. The aryl boronic acids derived from alkylation of these anions subsequently undergo a palladium mediated coupling with aryl halides to provide good yields of the desired biaryls. Copyright (C) 1996 Elsevier Science Ltd.
