Anand Devireddy, Patel Om P S, Maurya Rahul K, Kant Ruchir, Yadav Prem P
Medicinal and Process Chemistry Division, CSIR-Central Drug Research Institute , Lucknow-226031, India.
Molecular and Structural Biology Division, CSIR-Central Drug Research Institute , Lucknow-226031, India.
J Org Chem. 2015 Dec 18;80(24):12410-9. doi: 10.1021/acs.joc.5b02276. Epub 2015 Nov 20.
A phenyliodine(III) diacetate (PIDA)-mediated, highly efficient and tandem approach for the synthesis of aryldiazenylisoxazolo(isothiazolo)arenes from simple 2-amino-N'-arylbenzohydrazides has been developed. The reaction proceeds via formation of (E)-(2-aminoaryl)(aryldiazenyl)methanone as the key intermediate, followed by intramolecular oxidative O-N/S-N bond formation in one pot at room temperature. The quiet different reactivity of the substrate is due to the formation of a diazo intermediate which encounters a nucleophilic attack by carbonyl oxygen on the electrophilic amine to produce isoxazole products, as compared to the previous reportsa,b,4 in which an N-acylnitrenium ion intermediate is intramolecularly trapped by an amine group.
已开发出一种由二乙酸碘苯(III)(PIDA)介导的、高效的串联方法，用于从简单的2-氨基-N'-芳基苯甲酰肼合成芳基重氮基异恶唑(异噻唑)芳烃。该反应通过形成(E)-(2-氨基芳基)(芳基重氮基)甲酮作为关键中间体进行，随后在室温下一步一锅法进行分子内氧化O-N/S-N键的形成。底物截然不同的反应性是由于形成了一种重氮中间体，与之前的报道a、b、4相比，该中间体遇到羰基氧对亲电胺的亲核攻击，从而生成异恶唑产物，在之前的报道中，N-酰基氮鎓离子中间体被胺基分子内捕获。
