6327-79-3Relevant articles and documents
Rhodium-Catalyzed Aerobic Decomposition of 1,3-Diaryl-2-diazo-1,3-diketones: Mechanistic Investigation and Application to the Synthesis of Benzils
Zhu, Jia-Liang,Tsai, Yi-Ting
, p. 813 - 828 (2020/12/22)
The conversion of 1,3-diaryl-2-diazo-1,3-diketones to 1,2-daryl-1,2-diketones (benzils) is reported based on a rhodium(II)-catalyzed aerobic decomposition process. The reaction occurs at ambient temperatures and can be catalyzed by a few dirhodium carboxylates (5 mol %) under a balloon pressure of oxygen. Moreover, an oxygen atom from the O2 reagent is shown to be incorporated into the product, and this is accompanied by the extrusion of a carbonyl unit from the starting materials. Mechanistically, it is proposed that the decomposition may proceed via the interaction of a ketene intermediate resulting from a Wolff rearrangement of the carbenoid, with a rhodium peroxide or peroxy radical species generated upon the activation of molecular oxygen. The proposed mechanism has been supported by the results from a set of controlled experiments. By using this newly developed strategy, a large array of benzil derivatives as well as 9,10-phenanthrenequinone were synthesized from the corresponding diazo substrates in varying yields. On the other hand, the method did not allow the generation of benzocyclobutene-1,2-dione from 2-diazo-1,3-indandione because of the difficulty of inducing the initial rearrangement.
Non-metal catalytic method for preparing 1,3-diketone compounds based on acetyenic ketone
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Paragraph 0052-0055, (2020/02/19)
The invention discloses a non-metal catalytic method for preparing 1,3-diketone compounds based on acetyenic ketone. The preparation method is a stepwise method or a one-pot method. The stepwise method comprises the following steps: mixing an acetyenic ketone compound I, a nitrogen-containing aromatic compound II and a No.1 base for a reaction, performing separation and purification to obtain an intermediate product, mixing the intermediate product and a No.2 base for a reaction, and performing separation and purification to obtain the product; and the one-pot method comprises the following steps: firstly mixing an acetyenic ketone compound I and a nitrogen-containing aromatic compound II, adding a No.1 base, performing a reaction for a period of time, adding a No.2 base, continuing a reaction for a period of time, and finally performing separation and purification to obtain the product. The method provided by the invention has mild reaction conditions, simple operation and a higher yield, wherein the yield is generally 80% or more, and the method has greater practical application value in drug synthesis.
Novel Bifunctionalization of Activated Methylene: Base-Promoted Trifluoromethylthiolation of β-Diketones with Trifluoromethanesulfinyl Chloride
Sun, Dong-Wei,Jiang, Min,Liu, Jin-Tao
supporting information, p. 10797 - 10802 (2019/07/03)
A novel bifunctionalization of activated methylene was achieved successfully through the base-promoted trifluoromethylthiolation of β-diketones or β-ketoesters with trifluoromethanesulfinyl chloride. A series of α-trifluoromethylthiolated α-chloro-β-diketones and α-chloro-β-ketoesters were obtained in moderate to good yields under mild conditions. When β-diketones containing a phenyl group with a hydroxyl or amino substituent at the ortho position were used as substrates, intramolecular trifluoromethylthiolation/cyclization reaction took place to give the corresponding cyclic products. Furthermore, the protocol could be extended to perfluoroalkylthiolation with the sodium perfluoroalkanesulfinate/POCl3 system. On the basis of experimental results, plausible mechanisms are proposed.
