- Anti-Markovnikov stereoselective addition of bis(trimethylsilyl)octadiene to ketal obtained by unprecedented retro-Claisen condensation of 3-hydroxy-2,4-pentanedione bis-ketal
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In the course of the Lewis acid-mediated cycloaddition of 1,8-bis(trimethylsilyl)-2,6-octadiene to bis-ketals, we have observed an unprecedented retro-Claisen condensation from the ketalisation of a 3-hydroxy-2,4-pentadione giving rise to a substituted 2,
- Moraleda, Delphine,Galy, Nicolas,Brémond, Paul,Santelli, Maurice
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- FeCl3·6H2O-catalyzed selective conjugate reduction of alkylidene-β-keto esters and alkylidene-1,3-diketones
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FeCl3·6H2O/triethylsilane composite catalyst system is successfully developed for the selective conjugate reduction of carbon-carbon double bond of Michael acceptor-alkylidene-β-keto esters and alkylidene-1,3-diketones under mild rea
- Syamala, Lakshmi V.R. Babu,Mete, Trimbak B.,Bhat, Ramakrishna G.
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p. 3288 - 3291
(2018/07/25)
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- Rh(I) complexes bearing N, N and N,P ligands anchored on glassy carbon electrodes: Toward recyclable hydroamination catalysts
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A series of N,N-donor ligands (bis(pyrazol-1-yl)methane (bpm), bis(N-methylimidazol-2-yl)methane (bim), 1-(phenylmethyl)-4-(1H-pyrazol-1-yl methyl)-1H-1,2,3-triazole (PyT)), and one N,P-donor ligand precursor (1-(3,5-dimethylpyrazol-1-yl)(2-bromoethane) (dmPyBr)) were synthesized and functionalized with aniline. Diazotization of the aniline into an aryl diazonium, using nitrous acid in aqueous conditions, was performed in situ such that the ligands could be reductively adsorbed onto glassy carbon electrode surfaces. The N,N-donor ligands (bpm, bim, PyT) were immobilized in a single step, while several steps were required to immobilize the N,P-donor ligand (dmPyP) to prevent oxidation of the phosphine group. The complexation of the anchored ligands with the metal complex precursor ([Rh(CO)2(μ-Cl)] 2) led to the formation of anchored Rh(I) complexes with each of the ligands (bpm, bim, PyT, dmPyP). X-ray photoelectron spectroscopy (XPS) confirmed the formation of the anchored ligands as well as the anchored complexes. The surface coverage of functionalized electrodes was estimated by means of cyclic voltammetry, and the nature of the coverage was close to being a monolayer for each immobilized complex. The anchored Rh(I) complexes were active as catalysts for the intramolecular hydroamination of 4-pentyn-1-amine to form 2-methyl-1-pyrroline.
- Tregubov, Andrey A.,Vuong, Khuong Q.,Luais, Erwann,Gooding, J. Justin,Messerle, Barbara A.
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supporting information
p. 16429 - 16437
(2013/12/04)
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- NITROXYL ION SOURCE WITH SECOND ORDER REACTION NITROXYL RELEASE
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C-nitroso compound releases nitroxyl ion in blood in a second order reaction.
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Page/Page column 5
(2010/04/30)
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- TRIAZINE COMPOUNDS AND THEIR USE
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A compound of formula (I) wherein R1 is hydrogen, alkyl, -alkyl-aryl, -alkyl-heterocycloalkyl or -alkyl-0-heterocycloalkyl; R2 is hydrogen, hydroxy, amino, nitro, alkoxy, alkyl, aryl or heteroaryl; R3 is hydrogen, alkyl or
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- Cobalt-mediated alkylation of β-dicarbonyl compounds. Electrochemical evidence of cobalt(l) intermediate species and HPLC-MS detection of reaction intermediates
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The alkylation reactions of Co(II) acetylacetonate with alkyl halides are triggered by electrochemical reduction of the complex. This confirms Co(I) species as intermediates. HPLC-MS analysis of the reaction mixtures has permitted identification of some cobalt-containing intermediates involved in the alkylation reactions. Based on these results we propose a mechanistic hypothesis for the formation of dialkylation products and Co(III) acetylacetonate. Springer-Verlag Iberica 1997.
- Anhari,Gallardo,Vallribera
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- C-ALKYLATION OF β-DIKETONES WITH BENZYLPYRIDINIUM SALTS. EVIDENCE FOR CHAIN RADICAL MECHANISMS
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1-(p-Substituted benzyl)-2,4,6-triphenylpyridinium cations react with β-diketone anions by mechanisms which depend on the para-substituent.The p-methoxybenzyl derivative undergoes SN1 displacement yielding O- and C-benzylated products.The p-nitrobenzyl compound reacts by a chain radicaloid mechanism and gives high yields of C-p-nitrobenzylated diketones.The parent benzyl compound forms some C- and some O-benzylated products, together with bibenzyl, probably by a radical chain reaction which was suppressed by radical traps.
- Marquet, Jorge,Moreno-Manas, Marcial,Pacheco, Pedro,Prat, Maria,Katritzky, Alan R.,Brycki, Bogumil
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p. 5333 - 5346
(2007/10/02)
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- COBALT(II) CHLORIDE BISTRIPHENYLPHOSPHINE CATALYZED ALKYLATIONS OF β-DICARBONYL COMPOUNDS
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The alkylation of β-dicarbonyl compounds with several benzyl halides in chloroform and in the presence of potassium carbonate is accelerated by the presence of cobalt(II) chloride bistriphenylphosphine, thus broadening the scope of this alkylation method.
- Gonzalez, A.,Marquet, J.,Moreno-Manas, M
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p. 1469 - 1470
(2007/10/02)
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- A DUAL MECHANISTIC PATHWAY IN THE ALKYLATION OF PENTANE-2,4-DIONE THROUGH ITS Co(II) COMPLEX
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A mechanistic study on the alkylation of pentane-2,4-dione through its Co(II) complex has shown that a non radical chain mechanism initiated by an electron transfer step induced by Co(II) operates under certain experimental conditions.
- Marquet, J.,Moreno-Manas, M.,Pacheco, P.,Vallribera, A.
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p. 1465 - 1468
(2007/10/02)
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- ALKYLATION OF β-DIKETONES THROUGH THEIR Co(II), Co(III) AND Zn(II) COMPLEXES. 1-BROMOADAMANTANE AS ALKYLATING AGENT.
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α-(1-Adamantyl)-β-diketones are now accessible by the alkylation of Co(II) complexes of β-diketones with 1-bromoadamantane.The intermediacy of adamantyl cation is proposed.Co(II), Co(III) and Zn(II) complexes of pentane-2,4-dione react with alkyl halides precursors of stabilized carbenium ions, to give 3-alkylpentane-2,4-diones.
- Gonzalez, A.,Gueell, F.,Marquet, J.,Moreno-Manas, M.
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p. 3735 - 3738
(2007/10/02)
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