1817-57-8Relevant articles and documents
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Gamboni et al.
, p. 255,262 (1955)
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Mechanistic diversity of the selective oxidations mediated by supported iron phthalocyanine complexes
Perollier, Celine,Pergrale-Mejean, Corinne,Sorokin, Alexander B.
, p. 1400 - 1403 (2005)
Selective oxidations of (i) phenols and condensed aromatics to quinones and (ii) alkynes to α,β-acetylenic ketones mediated by supported iron phthalocyanine complexes exhibit very different mechanistic features as evidenced by 18O labelling and kinetic isotope effect studies. The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2005.
Preparation of α,β-acetylenic ketones by catalytic heterogeneous oxidation of alkynes
Perollier, Celine,Sorokin, Alexander B.
, p. 1548 - 1549 (2002)
Covalent grafting of iron phthalocyanines onto silica affords active catalysts for selective oxidation of alkynes and propargylic alcohols to α,β-acetylenic ketones, highly valuable precursors in the preparation of fine chemicals.
Propargylic C[sbnd]H activation using a Cu(II) 2-quinoxalinol salen catalyst and tert-butyl hydroperoxide
Black, Clayton C.,Gorden, Anne E.V.
, p. 803 - 806 (2018)
The oxidation of alkynes to α,β-acetylenic carbonyls was achieved using only 1 mol% of a Cu(II) 2-quinoxalinol salen catalyst with tert-butyl hydroperoxide. These reactions proceed under mild conditions (70 °C) with excellent selectivity, producing yields up to 78%, and were used on a variety of alkyne substrates to produce the desired corresponding α,β-acetylenic ketones. In addition, these reactions can be run under aqueous conditions using a sulfonated version of the 2-quinoxalinol salen with good yields, reducing the need for volatile organic solvents.
Synthesis of Highly Substituted Biaryls by the Construction of a Benzene Ring via in Situ Formed Acetals
Balamurugan, Rengarajan,Manojveer, Seetharaman,Tarigopula, Chandrahas
, p. 11871 - 11883 (2021/09/13)
Herein, we present an interesting method for the construction of a benzene ring using propargylic alcohols and 1,3-dicarbonyls, which involves three new C-C bond formations via cascade alkylation, formylation, annulation, and aromatization to make substituted biaryls. This one-pot Br?nsted acid-promoted protocol utilizes the unique reactivity of the acetal formed under the reaction conditions. Alkynyl methyl ketones could be employed instead of 1,3-dicarbonyls as they are converted to 1,3-dicarbonyls by hydration under the reaction conditions.
Fine-tuning dirhodium compounds with bridging ligands: Synthesis, structure, catalytic efficiency
Ning, Yangbo,Tan, Jiantao,Wang, Yuanhua,Wang, Zhifan
supporting information, (2021/09/28)
The structure of dirhodium compounds contains a unique Rh-Rh bond, two axial ligands and four bridging ligands. In the dirhodium(II) compounds, it is easy to migrate the coordinating atoms of the bridging ligand during the catalysis process, which leads to the degradation of the catalyst. Coordination atom migration was identified in bridging ligands. To improve the catalyst stability, we carried out a study on the effect of fine-tuning of the bridging ligand on the dirhodium compound. Several dirhodium compounds were designed and synthesized. During this process, we have successfully found Rh2(5-Br-esp)2 and Rh2(5-tBu-esp)2, which are closer to the ideal geometric configuration of the dirhodium(II) compounds. Rh2(5-Br-esp)2 has been applied in the oxidation of propargyl position and Rh2(5-tBu-esp)2 in the formation reaction of the C–N bond.
Oxidative Cleavage of Alkenes by O2with a Non-Heme Manganese Catalyst
Bennett, Elliot L.,Brookfield, Adam,Guan, Renpeng,Huang, Zhiliang,Mcinnes, Eric J. L.,Robertson, Craig M.,Shanmugam, Muralidharan,Xiao, Jianliang
supporting information, p. 10005 - 10013 (2021/07/19)
The oxidative cleavage of C═C double bonds with molecular oxygen to produce carbonyl compounds is an important transformation in chemical and pharmaceutical synthesis. In nature, enzymes containing the first-row transition metals, particularly heme and non-heme iron-dependent enzymes, readily activate O2 and oxidatively cleave C═C bonds with exquisite precision under ambient conditions. The reaction remains challenging for synthetic chemists, however. There are only a small number of known synthetic metal catalysts that allow for the oxidative cleavage of alkenes at an atmospheric pressure of O2, with very few known to catalyze the cleavage of nonactivated alkenes. In this work, we describe a light-driven, Mn-catalyzed protocol for the selective oxidation of alkenes to carbonyls under 1 atm of O2. For the first time, aromatic as well as various nonactivated aliphatic alkenes could be oxidized to afford ketones and aldehydes under clean, mild conditions with a first row, biorelevant metal catalyst. Moreover, the protocol shows a very good functional group tolerance. Mechanistic investigation suggests that Mn-oxo species, including an asymmetric, mixed-valent bis(μ-oxo)-Mn(III,IV) complex, are involved in the oxidation, and the solvent methanol participates in O2 activation that leads to the formation of the oxo species.