4211-89-6Relevant academic research and scientific papers
Monohydrochloride Assisted Synthesis of Functionalized Isoxazoles and Pyrazoles from Allenic Ketones: First Synthesis of (Z)-2-Methyl-7H-benzo[b]pyrazolo[5,1-d][1,5]oxazocines
Sarkar, Debayan,Sahoo, Sushree Ranjan
, p. 2035 - 2049 (2019/03/07)
A facile hydrochloride promoted regioselective synthesis of isoxazoles and pyrazoles from 1,2-allenic ketones is reported. The reaction has been scaled up to gram scale. A direct 8-endo dig ring annulations towards the first synthesis of (Z)-2-methyl-7H-b
Asymmetric Hydrogenation of Isoxazolium Triflates with a Chiral Iridium Catalyst
Ikeda, Ryuhei,Kuwano, Ryoichi
supporting information, p. 8610 - 8618 (2016/07/07)
The iridium catalyst [IrCl(cod)]2–phosphine–I2(cod=1,5-cyclooctadiene) selectively reduced isoxazolium triflates to isoxazolines or isoxazolidines in the presence of H2. The iridium-catalyzed hydrogenation proceeded in high-to-good enantioselectivity when an optically active phosphine–oxazoline ligand was used. The 3-substituted 5-arylisoxazolium salts were transformed into 4-isoxazolines with up to 95:5 enantiomeric ratio (e.r.). Chiral cis-isoxazolidines were obtained in up to 89:11 e.r., with no formation of their trans isomers, when the substrates had a primary alkyl substituent at the 5-position. The mechanistic studies indicate that the hydridoiridium(III) species prefers to deliver its hydride to the C5 atom of the isoxazole ring. The hydride attack leads to the formation of the chiral isoxazolidine via a 3-isoxazoline intermediate. Meanwhile, in the selective formation of 4-isoxazolines, hydride attack at the C5 atom may be obstructed by steric hindrance from the 5-aryl substituent.
An efficient synthesis of isoxazoles and pyrazoles under ultrasound irradiation
Huang, Zhi-Bin,Li, Li-Li,Zhao, Yan-Wei,Wang, Hui-Yuan,Shi, Da-Qing
, p. E309-E313 (2014/11/07)
A series of 5-arylisoxazole and 5-aryl-1H-pyrazole derivatives was synthesized by the reaction of 3-(dimethylamino)-1-arylprop-2-en-1-one with hydroxylamine hydrochloride or hydrazine hydrate under ultrasound irradiation without using any catalyst. This m
Clean and efficient synthesis of isoxazole derivatives in aqueous media
Dou, Guolan,Xu, Pan,Li, Qiang,Xi, Yukun,Huang, Zhibin,Shi, Daqing
, p. 13645 - 13653 (2014/01/06)
A series of 5-arylisoxazole derivatives were synthesized via the reaction of 3-(dimethyl-amino)-1-arylprop-2-en-1-ones with hydroxylamine hydrochloride in aqueous media without using any catalyst. This method has the advantages of easier work-up, mild rea
4-Chromenonyl-1,4-dihydropyridines and their use
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Page/Page column 31, (2010/02/17)
The present application relates to novel 4-chromenonyl-1,4-dihydropyridines, process for their preparation, their use for the treatment and/or prophylaxis of diseases, and their use for the manufacture of medicaments for the treatment and/or prophylaxis o
Reactivity of p-phenyl substituted β-enamino compounds using k- 10/ultrasound. II [1]. Synthesis of isoxazoles and 5-isoxazolones
Valduga, Claudete J.,Santis, Denise B.,Braibante, Hugo S.,Braibante, Mara E. F.
, p. 505 - 508 (2007/10/03)
The condensation of 4-phenyl substituted β-enamino ketones 1a-d and β- enamino esters 5a-d with hydroxylamine hydrochloride using K-10 as the solid support under sonication was studied to evaluate the formation of isoxazole and 5-isoxazolone rings from β-enamino compounds with a substituted aromatic ring. Isoxazoles 2a-c, 3c-d and 5-isoxazolones 6a-c and 7a-d were obtained. The use of K-10/ultrasound in this reaction furnished novel results in some cases.
An improved and effective method for the preparation of α,β- unsaturated oximes and isoxazole derivatives
Palacios, Francisco,Aparicio, Domitila,De Los Santos, Jesus M.,Rodriguez, Encina
, p. 599 - 614 (2007/10/03)
β-Functionalized oximes derived from phosphine oxides 5, phosphonates 8 and phosphonium salts 10 are easily obtained by simple addition of hydroxylamine compounds 2 to substituted allenes 3 and 6 or to propargylphosphonium salt 9. These oximo derivatives
Substituted 2,3-dihydroisoxazoles (Δ4-isoxazolines) via palladium- mediated cyclization of propargylic N-hydroxyureas
Stoner, Eric J.,Roden, Brian A.,Chemburkar, Sanjay
, p. 4981 - 4984 (2007/10/03)
Aryl-substituted propargylic N-hydroxyureas cyclize in the presence of catalytic Pd(OAc)2 to yield 2,3-dihydroisoxazoles.
Synthesis of 3-Substituted 5-Arylisoxazoles from α,β-Unsaturated Oximes
Alberola, Angel,Banez, J. Manuel,Calvo, Luis,Rodriguez, M. Teresa Rodriguez,Sanudo, M. Carmen
, p. 467 - 471 (2007/10/02)
The synthesis of 3-substituted 5-arylisoxazoles from oximes of α,β-unsaturated ketones is studied. The formation of the isoxazole derivatives takes place by cyclization of oximes in the presence of iodine and potassium iodide. The presence of isoxazoline
