Visible-Light-Induced Aerobic Oxidation of Benzylic C(sp3)–H of Alkylarenes Promoted by DDQ, tert-Butyl Nitrite, and Acetic Acid
作者:Zhenlu Shen、Decheng Pan、Yiqing Wang、Meichao Li、Xinquan Hu、Nan Sun、Liqun Jin、Baoxiang Hu
DOI:10.1055/s-0037-1610678
日期:2019.1
photocatalytic aerobic oxidation of benzylic C(sp3)–H bonds proceeded in the presence of 2,3-dichloro-5,6-dicyano-1,4-benzoquinone, tert-butyl nitrite, and acetic acid. Advantages of this aerobic oxidation method include its relatively mild conditions, the use of visible-light irradiation instead of conventional thermal methods, the use of a low catalyst loading, and the ability to oxidize a range of alkylarenes
Syntheses of 12<i>H</i>-benzo[<i>a</i>]xanthen-12-ones and benzo[<i>a</i>]acridin-12(7<i>H</i>)-ones through Au(<scp>i</scp>)-catalyzed Michael addition/6-<i>endo</i>-trig cyclization/aromatization cascade annulation
cascade cyclization strategy to synthesize both 12H-benzo[a]xanthen-12-ones and benzo[a]acridin-12(7H)-ones, whose core motifs xanthone and acridone both exist as important scaffolds in an immense number of bioactive compounds, was developed. The scopes of this strategy were examined by using a batch of synthetic 1,3-diphenylprop-2-yn-1-one substrates. To probe the mechanism of this cyclization a control
一种多面金(I)催化芳香性驱动的双6-内联双级环化策略,可合成其核心的12 H-苯并[ a ]黄嘌呤-12-酮和苯并[ a ] ac啶-12(7 H)-酮开发了基序黄酮和and啶酮,它们作为重要的支架存在于大量的生物活性化合物中。通过使用一批合成的1,3-二苯基丙-2-yn-1-one底物检查了该策略的范围。为了探索这种环化的机理,进行了合成中间体的对照实验。因此,根据该实验和先前的研究确定了推定的机制。
Synthesis of Xanthones, Thioxanthones and Acridones by a Metal-Free Photocatalytic Oxidation Using Visible Light and Molecular Oxygen
9H-Xanthenes, 9H-thioxanthenes and 9,10-dihydroacridines can be easily oxidized to the corresponding xanthones, thioxanthones and acridones, respectively, by a simple photo-oxidation procedure carried out using molecular oxygen as oxidant under the irradiation of visible blue light and in the presence of riboflavin tetraacetate as a metal-free photocatalyst. The obtained yields are high or quantitative