通过铬(II)的还原率,还原电位,电荷转移能和pK R +值测量的取代对甲基yl和环丙烯ium离子的稳定性参数之间的线性自由能关系
摘要:
已经合成了九个对yl离子,并测量了经验稳定性参数(i)-(iv)以及已知的对yl离子和环丙烯鎓离子的参数:(I)Cr(II)离子还原速率常数(k 2) 25.0°的10%盐酸水溶液; (ii)1,在1,2-二氯乙烷中的电荷转移频率(v CT max);(iii)在二氯甲烷或乙腈中的还原峰电位(E red);(iv)在23%的乙醇水溶液,50%的乙醇水溶液和50%的乙腈水溶液中的pK R +值。当检查了这些和先前报告的结果的线性自由能关系(LFER)(a)之间的电荷转移能量{(ECT)},119.5× v CT max(cm -1),kJ mol -1和E red {(96.36×E red(V),kj mol -1)};(b)在log k 2 {(5.70×log k 2(1 mol -1 s -1),kJ mol -1)}与E red之间;(c)在log k 2和E CT之间,发现令人满意的相互关系。
Gold Catalysts Can Generate Nitrone Intermediates from a Nitrosoarene/Alkene Mixture, Enabling Two Distinct Catalytic Reactions: A Nitroso-Activated Cycloheptatriene/Benzylidene Rearrangement
作者:Sayaji Arjun More、Rahul Dadabhau Kardile、Tung-Chun Kuo、Mu-Jeng Cheng、Rai-Shung Liu
DOI:10.1021/acs.orglett.1c01857
日期:2021.7.16
Gold-catalyzedreactions of cycloheptatrienes with nitrosoarenes yield nitrone derivatives efficiently. This reaction sequence enables us to develop gold-catalyzed aerobic oxidations of cycloheptatrienes to afford benzaldehyde derivatives using CuCl and nitrosoarenes as co-catalysts (10–30 mol %). Our density functional theory calculations support a novel nitroso-activated rearrangement, tropylium