Direct synthesis of anilines and nitrosobenzenes from phenols
作者:A. H. St. Amant、C. P. Frazier、B. Newmeyer、K. R. Fruehauf、J. Read de Alaniz
DOI:10.1039/c6ob00073h
日期:——
A one-pot synthesis of anilines and nitrosobenzenes from phenols has been developed using an ipso-oxidative aromatic substitution (iSOAr) process. The products are obtained in good yields under mild and metal-free conditions. The leaving group effect on reactions that proceed through mixed quionone monoketals has also been investigated and a predictive model has been established.
已经使用ipso-氧化性芳族取代(i S O Ar)方法开发了一种从苯酚一锅合成苯胺和亚硝基苯的方法。在温和且不含金属的条件下,可以以高收率获得产品。还研究了离去基团对通过混合的醌酮单缩酮进行的反应的影响,并建立了预测模型。
Direct Nitrosation of Aromatic Hydrocarbons and Ethers with the Electrophilic Nitrosonium Cation
作者:Eric Bosch、Jay K. Kochi
DOI:10.1021/jo00098a015
日期:1994.9
Various polymethylbenzenes and anisoles are selectively nitrosated with the electrophilic nitrosonium salt NO+ BFI4- in good conversions and yields under mild conditions in which the conventional procedure (based on nitrite neutralization with strong acid) is ineffective. The reactivity patterns in acetonitrile deduced from the various time/conversions in Tables 2 and 3 indicate that aromatic nitrosation is distinctly different from those previously established for electrophilic aromatic nitration. The contrasting behavior of NO+ in aromatic nitrosation is ascribed to a rate-limiting deprotonation of the reversibly formed Wheland intermediate, which in the case of aromatic nitration with NO2+ occurs with no deuterium kinetic isotope effect. Aromatic nitroso derivatives (unlike the nitro counterpart) are excellent electron donors that are subject to a reversible one-electron oxidation at positive potentials significantly less than that of the parent polymethylbenzene or anisole. As a result, the series of nitrosobenzenes are also much better Bronsted bases than the corresponding nitro derivatives, and this marked distinction, therefore, accounts for the large differentiation in the deprotonation rates of their respective conjugate acids (i.e. Wheland intermediates).
US8008303B2
申请人:——
公开号:US8008303B2
公开(公告)日:2011-08-30
[EN] 2,4-DIAMINOPHENOL DERIVATIVE, AND AGENT FOR INHIBITING AGGREGATION OF TAU AND/OR AMYLOID β<br/>[FR] DÉRIVÉ 2,4-DIAMINOPHÉNOL, ET AGENT D'INHIBITION DE L'AGRÉGATION DE TAU ET/OU DE L'AMYLOÏDE β<br/>[JA] 2,4-ジアミノフェノール誘導体、及び、タウ及び/又はアミロイドβの凝集阻害剤