7197-96-8Relevant articles and documents
Pincerlike manganese complex and preparation method thereof, related ligand and preparation method thereof, catalyst composition and application
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Paragraph 0159-0165, (2021/07/31)
The invention discloses a pincerlike manganese complex, a preparation method thereof, a ligand for preparation, a preparation method of the ligand, a catalyst composition taking the complex as an active component and application of the catalyst composition. According to the pincerlike manganese complex, a cycloalkyl ring is introduced into a ligand framework, and by regulating and controlling the cyclic tension, flexibility and steric hindrance of the cycloalkyl ring, the reactivity and stability of the manganese metal center can be effectively adjusted, and the catalytic activity and substrate applicability of a manganese metal system are remarkably improved. The catalyst composition taking the pincerlike manganese complex as an active component has the advantages of high catalyst activity, wide substrate application range, mild reaction conditions and the like in the process of preparing quinoline or pyridine derivatives by catalyzing dehydrogenation coupling reaction of o-amino aromatic alcohol or gamma-amino alcohol, ketone or secondary alcohol; and the synthesis advantages of low cost and stable performance are embodied, the operation is simple, and the yield is high.
Cu-Catalyzed Pyridine Synthesis via Oxidative Annulation of Cyclic Ketones with Propargylamine
Sotnik, Svitlana O.,Subota, Andrii I.,Kliuchynskyi, Anton Y.,Yehorov, Dmytro V.,Lytvynenko, Anton S.,Rozhenko, Alexander B.,Kolotilov, Sergey V.,Ryabukhin, Sergey V.,Volochnyuk, Dmitriy M.
, p. 7315 - 7325 (2021/05/29)
A Cu-catalyzed, easily scalable one-pot synthesis of fused pyridines by the reaction of cyclic ketones with propargylamine is described. The protocol was optimized based on the results of more than 30 experiments. The highest product yields were achieved in i-PrOH as a solvent in the presence of 5.0 mol % CuCl2 in air. In contrast to the well-known Au-catalyzed protocol, our procedure is "laboratory friendly", cost-effective, and suitable for preparing dozens of grams of fused pyridine-based building blocks and does not require a high-pressure autoclave technique. Decreasing the catalyst amount in the reaction to 1.25 mol % CuCl2 provided a yield comparable to that achieved with 5 mol % catalyst, though a longer reaction time was required. A plausible reaction mechanism was proposed. The scope and limitation of the reaction were studied using 24 different cyclic ketones as starting materials. The fused pyridine yield decreased among cyclic ketones in the following order: six-membered ? eight-membered > five-membered ~seven-membered. The elaborated reaction conditions demonstrated tolerance to a number of protective functional groups in ketone such as ester, tert-butoxycarbonyl (Boc)-protected amine, and acetal moieties.
Palladium acetate-catalyzed one-pot synthesis of mono- And disubstitued pyridines
Mikami, Shunya,Toyota, Masahiro
, p. 1315 - 1321 (2019/08/01)
A Pd-catalyzed one-pot synthesis of mono- and disubstituted pyridines was developed. The substituted pyridines were obtained from ketones or an aldehyde and 1,3-diaminopropane using a combination of catalytic Pd(OAc)2 and Cu(OAc)2. High-concentration reaction conditions enabled this catalytic reaction to be acid-free.