A Laser Flash Photolysis Study of Azo-Compound Formation from Aryl Nitrenes at Room Temperature
作者:Alec Q. Ribblett、James S. Poole
DOI:10.1021/acs.jpca.6b03025
日期:2016.6.30
1-oxide, are useful models to probe the mechanism of formation of azo-dimers, which is postulated to proceed by self-reaction of the nitrene or reaction of nitrene with the parent azide. A laser flashphotolysisstudy is described where the kinetics of formation of azo-dimer were found to be most adequately modeled by competition between both mechanisms, and rate coefficients for the competing reactions
Kinetic and mechanistic studies of the Staudinger reduction: On the chemistry of aryl phosphazides
作者:Samantha Y. Corrigan、James S. Poole
DOI:10.1002/poc.4442
日期:2023.2
The Staudingerreduction of heteroaryl azides containing an N-oxide moiety with triphenylphosphine in mixed aqueous/THF solutions yields a mixture of amine and iminophosphorane products. A product analysis study using a combination of 1H and 31P NMR spectroscopic techniques indicates that in these systems, even under mild conditions, the amine product is generated, not from the hydrolysis of the iminophosphorane
在混合水溶液/THF 溶液中,用三苯基膦对含有N-氧化物部分的杂芳基叠氮化物进行施陶丁格还原,得到胺和亚氨基正膦产物的混合物。结合使用1 H 和31 P NMR 光谱技术进行的产物分析研究表明,在这些系统中,即使在温和条件下,胺产物的产生也不是标准反应机制所预期的亚氨基正膦的水解,而是通过磷酰肼中间体的水解。生成的胺的量取决于起始叠氮化物的结构、溶剂的组成和反应条件。讨论了酸性、中性和碱性条件下胺形成的可能机制。
作者:Katherine J. Hostetler、Kyle N. Crabtree、James S. Poole
DOI:10.1021/jo061259o
日期:2006.11.1
Laser flash photolysis of 4-azidopyridine-1-oxide at 266 or 308 nm yields triplet 4-nitrenopyridine-1-oxide as the dominant reactive intermediate species, with k(ISC) of approximately 2 x 10(7) s(-1). No evidence of products arising from the singlet nitrene was observed, indicating a slow rate of cyclization to the benzazirine and didehydroazepine species. The slow rate of cyclization is postulated to be due to the aminoxyl-like electronic configuration of this species, which withdraws spin density from sites for potential cyclization.