Copper catalyzed cross-coupling reactions of diaryl ditellurides with potassium aryltrifluoroborate salts

Alves, Diego; Pena, Jesus M.; Vieira, Adriano S.; Botteselle, Giancarlo V.; Guadagnin, Rafael C.; Stefani, Hélio A.

doi:10.1590/s0103-50532009000500025

Cited by 21 publications

(11 citation statements)

References 19 publications

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“…Alves and co–workers were able to cross couple aryltrifluoroborates with diarylditellurides using similar reactions conditions mentioned above, (Scheme 198). 409 Catalyst loading could be reduced from 10 mol% to 5 and 1 mol% without decreasing yields. In contrast to Taniguchi protocol, this reaction is sensitive to electronic effects of the aromatic ring of the trifluoroborate salts.…”

Section: Reaction Of Carbanions and Carbanion Equivalentsmentioning

confidence: 99%

Aerobic Copper-Catalyzed Organic Reactions

et al. 2013

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24 peroxide [Cu I (pyr)(tpb)] 10 mol % TBHP, 1 atm O 2 , 1:2 AcOH/pyr, rt, 24 h ∼2.5 26 74 g 35 25 n-hexane aldehyde CuCl 2 , 18-crown-6 1 atm O 2 , MeCHO, CH 2 Cl 2 , 70 °C, 24 h 2.4 91 h 9 34a 26 n-decane aldehyde Cu II Cl 16 Pc-AM(PS) 3 equiv of PhCHO, MeCN, 1 atm O 2 , 50 °C 15.4 100 i 61 a See Chart 2 for ligand structures. b Also 28% cyclohexene. c Also 26% cyclohexene. d Mixture of alcohol and hydroperoxide. e Remainder of product is cyclohexene. f Approximately 93:7 of 1-adamantol/2-adamantol. g Approximately 98:2 of 1-adamantol/2-adamantol. h Afforded oxidation products in an approximately 1:1 ratio at the 2-and 3-positions. i Mixture of decanones.

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Section: Reaction Of Carbanions and Carbanion Equivalentsmentioning

confidence: 99%

Aerobic Copper-Catalyzed Organic Reactions

et al. 2013

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“…38 Organotellurides are known to present higher reactivity in relation to the structurally related organoselenium compounds due to their higher electronegativity in relation to carbon, which is associated with a larger atomic volume. 39,40 Furthermore, the introduction of methyl group in OS2 increases only the cytotoxicity of the compound without effect on the mutagenic properties.…”

Section: Discussionmentioning

confidence: 99%

Genetic toxicity of three symmetrical diselenides in yeast

Rosa¹,

Guecheva²,

Oliveira³

et al. 2010

J. Braz. Chem. Soc.

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O disseleneto de difenila (DPDS) é um reagente eletrofílico empregado na síntese de diversos compostos organoselenados (OS) farmacologicamente ativos. O objetivo do presente estudo foi investigar os efeitos mutagênicos de três derivados simétricos do DPDS (p-cloro-fenil-disseleneto, p-metil-fenil-disseleneto e p-metoxi-fenil-disseleneto) em levedura. Em resumo, os efeitos celulares dos três OS estudados nesse trabalho parecem ser variáveis em função do grupo químico substituinte no anel aromático e da concentração empregada. A presença de grupo metila no anel aromático do DPDS aumenta o potencial citotóxico enquanto a inserção de um grupamento metoxila potencializa os efeitos citotóxicos e mutagênicos do DPDS.Diphenyl diselenide (DPDS) is an electrophilic reagent used in the synthesis of a variety of pharmacologically active organoselenium (OS) compounds. The aim of the present study was to investigate the mutagenic effects of three symmetrical derivatives from the prototype DPDS (p-chloride-phenyl-diselenide, p-methyl-phenyl-diselenide and p-methoxy-phenyl-diselenide) in yeast. In summary, the cellular effects of the three OS compounds studied in this work appear to be variable according to the substituent group in the aromatic ring and are concentration-dependent. The presence of methoxyl group in the aromatic ring of DPDS structure results in elevation of the cytotoxic and mutagenic potential while the introduction of a methyl group increases the cytotoxic effect. Keywords: organoselenium, diphenyl diselenide, Saccharomyces cerevisiae IntroductionSelenium, an essential trace element for animals, is known to have antioxidant and chemopreventive potential in numerous animal model systems as well as cancer chemopreventive efficacy in humans. 1-5 Ingestion of the major known dietary sources of selenium, such as selenomethionine, selenocysteine and inorganic selenium is limited by toxicity. Thus, a number of synthetic derivatives have been developed. In the last few decades, the interest in organoselenium (OS) biochemistry has intensified due to variety of pharmacologic effects of the synthetic OS compounds. The above molecules could be used as antioxidants, enzyme inhibitors, neuroprotective agents, anti-tumor and anti-infectious agents, cytokine inducers and immunomodulators. 6,7 Diphenyl diselenide (DPDS, Figure 1) is a simple and stable OS compound. It is an electrophilic reagent used in the synthesis of a variety of pharmacologically active OS compounds. 8,9 Indeed, the biological activity of DPDS has been studied and this compound has become a good candidate for therapeutic proposals, since it presents very interesting pharmacological effects. When compared to other tested diselenide substitutes or ebselen, DPDS exhibits high thiol peroxidase activity and better antioxidant potential as a glutathione peroxidase mimic. 2 It furthermore has neuroprotective, anti-inflammatory and hepatoprotective properties. 8,10 However, DPDS also presents toxic effects as it inhibits d-aminolevulinate dehydratase in several ...

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“…[30][31][32][33][34] All the products, except di(4-carbomethoxyphenyl)telluride, are known and were identified by co-TLC with authentic samples and by mp, IR and NMR spectra which are in good agreement with reported literature. [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29] General Procedure of Deoxygenation of Telluroxides. In a typical experiment, di(4-tolyl)telluroxide (1 mmol, 0.325 g), anhydrous nickel chloride (1 mmol, 0.129 g) and dry THF (10 mL) with a stir bar and were placed in a 50 mL RB flask, fitted with a condenser and calcium chloride guard tube.…”

Section: Methodsmentioning

confidence: 99%