914-15-8Relevant academic research and scientific papers
Efficient synthesis of novel 5-phenylsulfonyl-substituted 4,5-dihydro-1Hpyrazolo[ 3,4-b]pyridines
Fan, Ling,Ruan, Chengcheng,Guo, Binghuang,Tang, Xiwu,Xia, Peng
, p. 591 - 593 (2016)
An efficient method for the synthesis of novel 5-phenylsulfonyl substituted 4,5-dihydro-1H-pyrazolo[3,4-b]pyridines from 5-Aminopyrazoles, aldehydes and β-ketosulfones in refluxing acetic acid is described. The X-ray crystallographic structure of the prod
A mild method for the synthesis of bis-pyrazolo[3,4-b:4′,3′-e]pyridine derivatives
Qiu, Rui,Qiao, Shujia,Peng, Boyu,Long, Jiajia,Yin, Guodong
supporting information, p. 3884 - 3888 (2018/09/27)
A mild and efficient method for the synthesis of bispyrazolo[3,4-b:4′,3′-e]pyridines from 5-aminopyrazoles and aromatic aldehydes using an inexpensive FeCl3 catalyst is reported. The reaction temperature was reduced from 220–250 °C to 130 °C compared to conventional methods. A large proportion of the products precipitated directly from the mixture at room temperature. Aliphatic and α,β-unsaturated aldehydes selectively resulted in formation of the corresponding 1H-pyrazolo[3,4-b]pyridine derivatives. A possible domino reaction mechanism was also proposed. Several aryl alkynyl groups were introduced to these tricyclic molecules via the Sonogashira coupling reaction.
Solvent-free microwave synthesis of bis-pyrazolo[3,4-b:4′,3′-e] pyridines and study of their antifungal properties
Quiroga,Portilla,Insuasty,Abonia,Nogueras,Sortino,Zacchino
, p. 61 - 66 (2007/10/03)
The synthesis of a series of bis-pyrazolo[3,4-b:4′,3′-e] pyridines (3) in the reaction of 5-amino-3-methyl-1-phenylpyrazole (1) with aldehydes (2) under microwave irradiation and solvent-free conditions is described. The structure elucidation of the produ
Synthesis of Benzylidenaminopyrazoles and Bispyrazolopyridines
Hennig, L.,Hofmann, J.,Alva-Astudillo, M.,Mann, G.
, p. 351 - 358 (2007/10/02)
5-Aminopyrazoles 1a-e react with aromatic aldehydes in boiling ethanol to yield azomethines 2a-n.Bispyrazolopyridines 7a-f are obtained by the reaction of 2a-f with an excess of aminopyrazole at higher temperatures via bisaminopyrazoles 5 and bispyrazolodihydropyridines 6.Structure and configuration of the products are assigned by n.m.r. spectroscopy.Reactions with replacement of the arylidene group on azomethine 2b suggest that the transformation of azomethines to bisaminopyrazoles occurs through a mechanism involving addition of the CH-acidic component, with subsequent elimination of aminopyrazole.
Synthesis of Pyrazoloquinolines from 4-Aroyl-5-chloropyrazoles
Hennig, L.,Mueller, T.,Grosche, M.
, p. 693 - 698 (2007/10/02)
The reaction of 4-aroyl-5-chloro-3-methyl-1-phenyl-pyrazoles 1 with an excess of 3- or 4-substituted and 3,4-disubstituted anilines 2 gives pyrazoloquinolines 4a-k.Information about the reaction mechanism was obtained by the isolation of the intermediate product 3e.In some cases it was possible to isolate subsequent products 4l-p.The reaction of 1a with 5-amino-3-methyl-1-phenyl-pyrazole (5) gives a bispyrazolopyridine derivative 6.
