76893-72-6Relevant academic research and scientific papers
Acridine Orange Hemi(Zinc Chloride) Salt as a Lewis Acid-Photoredox Hybrid Catalyst for the Generation of α-Carbonyl Radicals
Das, Sanju,De Sarkar, Suman,Mandal, Tanumoy
supporting information, (2021/12/10)
A readily accessible organic-inorganic hybrid catalyst is reported for the reductive fragmentation of α-halocarbonyl compounds. The robust hybrid catalyst is a self-stabilizing combination of ZnCl2 Lewis acid and acridine orange as the photoactive organic dye. Mechanistic specifics of this hybrid catalyst have been studied in detail using both photophysical and electrochemical experiments. A systematic study enabled the discovery of the appropriate Lewis acid for the effective LUMO stabilization of α-halocarbonyl compounds and thereby lowering of reduction potential within the range of a standard organic dye. This strategy resolves the issues like dehalogenative hydrogenation or homo-coupling of alkyl radicals by guiding the photoredox cycle through an oxidative quenching pathway. The cooperativity between the photoactive organic dye and the Lewis acid counterparts empowers functionalization with a wide range of coupling partners through efficient and controlled generation of alkyl radicals and serves as an appropriate alternative to the expensive late transition metal-based photocatalysts. To demonstrate the application potential of this cooperative catalytic system, four different synthetic transformations of α-carbonyl bromides were explored with broad substrate scopes.
Rhodium-Catalyzed Rearrangement of S/Se-Ylides for the Synthesis of Substituted Vinylogous Carbonates
Reddy, Angula Chandra Shekar,Anbarasan, Pazhamalai
supporting information, p. 9965 - 9969 (2019/12/24)
An efficient rhodium-catalyzed unprecedented oxa-[2,3]-sigmatropic rearrangement of sulfur ylide derived from α-thioesters/ketones and diazo carbonyl compounds has been accomplished for the synthesis of various sulfur-tethered vinylogous carbonates in good to excellent yields. Important features of the developed reaction include wide functional group tolerance, excellent chemo- and regioselectivity, and efficient rearrangement involving the carbonyl motif. The present reaction also equally works well with α-selenoesters for the synthesis of seleno-containing vinylogous carbonates.
Synthesis and evaluation of dual site inhibitors of 3-deoxy-d-arabino- heptulosonate 7-phosphate synthase
Walker, Scott R.,Jiao, Wanting,Parker, Emily J.
supporting information; experimental part, p. 5092 - 5097 (2011/10/09)
3-Deoxy-d-arabino-heptulosonate 7-phosphate (DAH7P) synthase catalyses the first step of the shikimate pathway for the biosynthesis of aromatic compounds. Enzymes of this pathway have been identified as potential targets for drug design. The reaction catalysed by DAH7P synthase is an aldol condensation between phosphoenolpyruvate (PEP) and d-erythrose 4-phosphate (E4P). In this study inhibitors of DAH7P synthase were prepared which were designed to fit into the binding sites of both PEP and E4P substrates simultaneously. Inhibitors, known to target the PEP binding site, were extended using a C4 linker to include an appropriately placed phosphate group in order to access the phosphate-binding site of E4P. A small increase in inhibition was observed with this modification, and the inhibition results have been rationalised by induced-fit docking.
Fluorinations of α-seleno carboxylic acid derivatives with hypervalent (difluoroiodo)toluene
Arrica, Maria A.,Wirth, Thomas
, p. 395 - 403 (2007/10/03)
A very efficient synthesis of (difluoroiodo)toluene avoiding the use of elemental chlorine and elemental fluorine is described. We have fluorinated a series of α-acceptor substituted selenides using (difluoroiodo)toluene. The reactions are usually very clean and under the reaction conditions no further oxidized products are observed. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005.
General synthesis of alkyl phenyl selenides from organic halides mediated by zinc in aqueous medium
Bieber, Lothar W.,De Sá, Ana C.P.F.,Menezes, Paulo H.,Gon?alves, Simone M.C.
, p. 4597 - 4599 (2007/10/03)
Organic halides of different structural types react with diphenyl diselenide and zinc dust in aqueous medium to give alkyl phenyl selenides. Benzylic and allylic bromides, α-bromoesters, acids and ketones and some primary alkyl iodides produce high yields even under acidic conditions. Less reactive halides need basic medium. The reaction proceeds equally well in the presence of various unprotected functional groups. Control experiments support a SH2 mechanism via alkyl radicals.
Preparation and oxidation of α-phenylselanyl esters
Lebarillier, Loic,Outurquin, Francis,Paulmier, Claude
, p. 7483 - 7493 (2007/10/03)
Alkylation and selenenylation of selenium-stabilized ester enolates have allowed the preparation of α-phenylselanyl esters 5, 7, 8 and of α,α-bis(phenylselanyl)esters 6, respectively. The competitive selenophilic reaction, leading to an allylic phenylselenide 9, was avoided in the presence of HMPA. α-phenylselanyl α,β-unsaturated esters 15 were prepared by oxidation of compounds 6 and dehydrohalogenation of β-chloroesters 17. Some other transformations: oxidation, transesterification and Grignard reaction were also studied. H2O2 oxidation of Z-esters 15 has led to stable E-α-seleninyl esters 20. (C) 2000 Elsevier Science Ltd.
Synthesis of allyl-type selenides and α -selenoesters in aqueous media promoted by cadmium
Zheng, Yunfa,Bao, Weiliang,Zhang, Yongmin
, p. 1731 - 1736 (2007/10/03)
Promoted by metallic cadmium which was produced by reduction of CdCl2 · H2O with samarium in situ, allyl bromide and α -bromocarboxylates react with diorgano diselenides in aqueous solutions to give allylic-type selenides and α -selenocarboxylates in moderate to good yields.
A STEREOSELECTIVE SYNTHESIS OF THE C-15 TO C-20 SEGMENT OF RIFAMYCIN-S
Rama Rao, A. V.,Yadav, J. S.,Srinivasa Rao, C.
, p. 3297 - 3298 (2007/10/02)
A convenient method has been described for the stereoselective construction of 5-substituted-2-methyl-2Z,4E-pentadienoic acid, present in the ansa bridge of rifamycin-S.
ALKENE CARBOSULPHENYLATION AND CARBOSELENYLATION: THE USE OF ALLYLTRIMETHYLSILANE AND O-SILYLATED ENOLATES.
Alexander, Rikki P.,Paterson, Ian
, p. 5911 - 5914 (2007/10/02)
Allyltrimethylsilane, as well as O-silylated enolates, can be alkylated by the PhSCl adducts of alkenes and vinyl ethers (1, X=SPh); the PhSeCl analogues (1, X=SePh), however, are less useful for alkylation purposes due to competing nucleophilic attack at selenium.
