- ORGANOBORON COMPOUNDS. CDXIV. HOMOLOGATION OF 3-METHOXY-7-METHYL-3-BORABICYCLONONANE AND 3-METHOXY-7-METHOXYMETHYL-3-BORABICYCLONON-6-ENE USING α-HALOALKYLLITHIUM COMPOUNDS. SYNTHESIS OF 3-BORABICYCLODECANE AND 3-BORABICYCLODEC-7(8)-ENE DERIVATIVES
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3-Methoxy-7-methyl-3-borabicyclononane (I) and 3-methoxy-7-methoxymethyl-3-borabicyclonon-6-ene (X) react with α-halomethyllithium compounds at decane and a mixture of 3-methoxy-8-methoxymethyl-3-borabicyclodec-7-ene and 3-methoxy-8-methoxymethyl-3-borabicyclodec-8-ene.A similar reaction of I or X with α-bromomethyllithium leads to the corresponding endo-4- and exo-4-methyl derivatives of 3-borabicyclodecane and 3-borabicyclodec-7(8)-ene.
- Gurskii, M. E.,Baranin, S. V.,Mikhailov, B. M.
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- Polysilane-Immobilized Rh-Pt Bimetallic Nanoparticles as Powerful Arene Hydrogenation Catalysts: Synthesis, Reactions under Batch and Flow Conditions and Reaction Mechanism
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Hydrogenation of arenes is an important reaction not only for hydrogen storage and transport but also for the synthesis of functional molecules such as pharmaceuticals and biologically active compounds. Here, we describe the development of heterogeneous Rh-Pt bimetallic nanoparticle catalysts for the hydrogenation of arenes with inexpensive polysilane as support. The catalysts could be used in both batch and continuous-flow systems with high performance under mild conditions and showed wide substrate generality. In the continuous-flow system, the product could be obtained by simply passing the substrate and 1 atm H2 through a column packed with the catalyst. Remarkably, much higher catalytic performance was observed in the flow system than in the batch system, and extremely strong durability under continuous-flow conditions was demonstrated (>50 days continuous run; turnover number >3.4 × 105). Furthermore, details of the reaction mechanisms and the origin of different kinetics in batch and flow were studied, and the obtained knowledge was applied to develop completely selective arene hydrogenation of compounds containing two aromatic rings toward the synthesis of an active pharmaceutical ingredient.
- Miyamura, Hiroyuki,Suzuki, Aya,Yasukawa, Tomohiro,Kobayashi, Shu
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supporting information
p. 11325 - 11334
(2018/09/06)
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- METHODS FOR SELECTIVELY HYDROGENATING SUBSTITUTED ARENES WITH SUPPORTED ORGANOMETALLIC CATALYSTS
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Methods for selectively hydrogenating substituted arenes with a supported organometallic hydrogenating catalyst are provided. An exemplary method includes contacting a substituted arene-containing reaction stream with hydrogen in the presence of a supported organometallic hydrogenating catalyst under reaction conditions effective to selectively hydrogenate the substituted arenes to the cis isomer with high selectivity. In this method, the supported organometallic hydrogenating catalyst includes a catalytically active organometallic species and a Br?nsted acidic sulfated metal oxide support.
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Paragraph 0037
(2016/06/28)
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- Catalytic hydrogenation of aromatics under biphasic conditions: Isolation and structural characterisation of the cluster intermediate [(η6-C6Me6)2(η 6-C6H6)Ru3(μ2-H) 2(μ2-OH)(μ3-O)]+
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The water-soluble cluster cation [(η6-C6Me6)2(η 6-C6H6)Ru3(μ2-H) 3(μ3-O)]+ (2) catalyses the hydrogenation of benzene and benzene derivatives to give the corresponding cyclohexanes under biphasic conditions. The catalytic activity of 2 depends markedly on the substrate, an extremely high activity being observed for ethylbenzene. The cationic species present in the catalytic mixture of the ethylbenzene hydrogenation could be isolated as the tetrafluoroborate salt and characterised as the cation [(η6-C6Me6)2(η 6-C6H6)Ru3(μ2-H) 2(μ2-OH)(μ3-O)]+ (3). With 3 as the catalyst, the catalytic activity is also much higher for other benzene derivatives.
- Faure, Matthieu,Vallina, Ana Tesouro,Stoeckli-Evans, Helen,Süss-Fink, Georg
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p. 103 - 108
(2007/10/03)
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