78830-50-9Relevant academic research and scientific papers
Method for synthesizing 4-acyl pyrazole compound from non-cyclic ketone hydrazone
-
Paragraph 0058; 0059; 0060, (2017/09/26)
The invention discloses a method for synthesizing a 4-acyl pyrazole compound from non-cyclic ketone hydrazine, and belongs to the technical field of organic synthesis. The technical scheme of the invention is characterized in that the method for synthesizing the 4-acyl pyrazole compound from the non-cyclic ketone hydrazine specifically comprises the following steps: dissolving an alpha,beta-saturated ketone compound in a solvent; adding a catalyst, a ligand and an oxidizing agent in sequence; stirring for reacting at the temperature of 100 to 140 DEG C in a nitrogen atmosphere; then, adding the non-cyclic ketone hydrazine into a reaction system; continually reacting at the temperature of 100 to 140 DEG C in an air atmosphere to obtain the 4-acyl pyrazole compound. By adopting the method, the alpha,beta-saturated ketone compound and the non-cyclic ketone hydrazine are subjected to a one-pot multi-step serial reaction under the catalysis of a copper salt to obtain the 4-acyl pyrazole compound; the method has the advantages of easiness and convenience in operation, mild conditions and wide substrate application range, and the suitable for industrial production.
Synthesis of 4-Acylpyrazoles from Saturated Ketones and Hydrazones Featured with Multiple C(sp3)-H Bond Functionalization and C-C Bond Cleavage and Reorganization
Tian, Miaomiao,Shi, Xiaonan,Zhang, Xinying,Fan, Xuesen
, p. 7363 - 7372 (2017/07/26)
In this paper, an efficient and convenient one-pot synthesis of diversely substituted 4-acylpyrazole derivatives via copper-catalyzed one-pot cascade reactions of saturated ketones with hydrazones is reported. Mechanistically, the formation of the title compounds involves the in situ formation of an enone intermediate through the dehydrogenation of a saturated ketone and the [2 + 3] cyclization of the enone with hydrazone followed by an aromatization-driven C-C bond cleavage and reorganization. To our knowledge, this is the first example in which the biologically and pharmaceutically important yet otherwise difficult-to-obtain 4-acylpyrazole derivatives are directly prepared from saturated ketones and hydrazones featured with multiple aliphatic C-H bond functionalization and C-C bond cleavage and reorganization. Compared with literature methods, this novel process has advantages such as simple and economical starting materials, a sustainable oxidant, excellent regioselectivity, and good efficiency.
The Cycloaddition of Nitrilimines with 1,2-Dibenzoylethylenes
Oida, Tatsuo,Shimizu, Tomio,Hayashi, Yoshiyuki,Teramura, Kazuhiro
, p. 1429 - 1433 (2007/10/02)
The cycloaddition of nitrimines with 1,2-dibenzoylethylenes gave an unexpected 1,3-diaryl-4-benzoylpyrazole and benzoic acid, along with an expected cycloadduct, 1,3-diaryl-4,5-dibenzoyl-2-pyrazoline, and its dehydrogenated product, 1,3-diaryl-4,5-dibenzoylpyrazole.The elimination of the benzoyl group from the pyrazoline followed by dehydrogenation was shown to be the course of the unusual reaction.
