59563-52-9Relevant academic research and scientific papers
Studies on Pyrazolopyrimidine Derivatives. XV. Reactions Involving the Formation of the Anion of the Reissert Compound Derived form 1H-Pyrazolopyrimidine
Hagishino, Takeo,Sato, Susumu,Miyashita, Akira,Katori, Tatsuhiko
, p. 4078 - 4086 (2007/10/02)
The anion (A) of the Reissert compound (1, 5-benzoyl-4,5-dihydro-1-phenyl-1H-pyrazolopyrimidine-4-carbonitrile) was found to react with electrophiles in two ways.One is nucleophilic attack of the anion A.The other is self-decomposition of the anion A.Thus, A underwent nucleophilic attack with aromatic and aliphatic aldehydes (4a-j), resulting in the formation of the corresponding α-aryl (or alkyl)-1-phenyl-1H-pyrazolopyrimidin-4-ylmethyl benzoates (6a-j) together with 1-phenyl-1H-pyrazolopyrimidine (2), the 4,4'-dimer (7) of 2, O-benzoylaroins (8a-d), and O-benzoylcyanohydrins (9e-j).Nucleophilic substitution took place in the reaction of A with 2,4-dinitrochlorobenzene (14a) and methyl iodide (14d), giving the 4-(2,4-dinitrophenyl) derivative (17a) of 2 and 5,7-dibenzoyl-4-methyl-1-phenyl-4-(1-phenyl-1H-pyrazolopyrimidin-4-yl)-4,5,6,7-tetrahydro-1H-pyrazolopyrimidine-6-carbonitrile (19), respectively.However, the anion A did not react with other aryl (or alkyl) halides (14b, c, e), ketones (11a, b), 2-alkenonitriles (21a, b), and dimethylacetylenedicarboxylate (22), and underwent the known self-decomposition, resulting in the formation of products such as 2, 7, the cyano derivative (18) of 2, and the ester 6a.Keywords - pyrazolopyrimidine; Reissert compound; aldehyde; aryl halide; nucleophilic attack; self-decomposition; pyrazolopyrimidinemethanol
Studies on Pyrazolopyrimidine Derivatives. XIV. Preparation and Reactions of 1-Phenyl-1H-pyrazolo-pyrimidine Reissert Compound
Higashino, Takeo,Sato, Susumu,Miyashita, Akira,Katori, Tatsuhiko
, p. 4569 - 4576 (2007/10/02)
The Reissert reaction of 1-phenyl-1H-pyrazolopyrimidine (4) in anhydrous methylene chloride using benzoyl chloride, trimethylsilyl cyanide, and a catalytic amount of aluminium chloride gave the corresponding Reissert compound (3, 5-benzoyl-4,5-dihydro-1-phenyl-1H-pyrazolopyrimidine-4-carbonitrile) in 95percent yield.The alkaline hydrolysis of 3 in methanol resulted in the formation of 4, benzoic acid (7), and the 4,4'-dimer (9) of (4).The acid hydrolysis in dimethyl sulfoxide and in methanol proceeded with ring fission to give 5-amino-α-benzamido-1-phenyl-1H-pyrazole-4-acetonitrile (13), the acetamide (14), and the acetate (15).Compound 3 reacted with sodium hydride in dimethylformamide to give 4, 9, 1-phenyl-1H-pyrazolopyrimidine-4-carbonitrile (20), α,1-diphenyl-1H-pyrazolopyrimidin-4-ylmethyl benzoate (21), and O-benzoylmandelonitrile (22).In the present paper, we compare the chemical properties of 3 with those of the isoquinoline Reissert compound (1, 2-benzoyl-1,2-dihydro-1-isoquinolinecarbonitrile).Keywords-pyrazolopyrimidine Reissert compound; preparation; chemical property; hydrolysis; pyrazoleacetonitrile; carbanion; rearrangement; pyrazolopyrimidinemethanol
Transformation of Quinazoline into 2(1H)-Quinolinones with Alkanoic Anhydrides
Higashino, Takeo,Goto, Ayako,Miyashita, Akira,Hayashi, Eisaku
, p. 4352 - 4355 (2007/10/02)
Quinazoline (1) was transformed into 3-substituted 2(1H)-quinolinones (4) by reaction with alkanoic anhydrides (3).Similar transformation was also found to occur with 5-methyl-1-phenyl-1H-pyrazolopyrimidinium iodide (9), giving 5-substituted 1-phenyl-1H-pyrazolo-pyridine-6-yl alkanoates (10).Keywords-quinazoline; quinolinone; alkanoic anhydride; ring transformation; pyrazolo-pyrimidinium salt; pyrazolopyridine
