Sequential Oxidative Fragmentation and Skeletal Rearrangement of Peroxides for the Synthesis of Quinazolinone Derivatives
作者:Akash S. Ubale、Moseen A. Shaikh、Boopathy Gnanaprakasam
DOI:10.1021/acs.joc.1c00889
日期:2021.7.16
For the first time, the sequential reaction of peroxyoxindole that involves base-promoted oxidative fragmentation to isocyanate formation and primary amine or amino alcohol accelerated skeletal rearrangement to synthesize exo-olefinic-substituted quinazolinone or oxazoloquinazolinone is reported. The advantages of this new reaction include a broad substrate scope and transition-metal-free and room-temperature
Environmentally Benign Synthesis of Quinoline–Spiroquinazolinones by Iron-Catalyzed Dehydrogenative [4 + 2] Cycloaddition of Secondary/Tertiary Anilines and 4-Methylene-quinazolinones
作者:Yuxin Ding、Jinqiang Kuang、Xuqiong Xiao、Lei Wang、Yongmin Ma
DOI:10.1021/acs.joc.1c01602
日期:2021.9.3
We report an efficient iron-catalyzed cross-dehydrogenative coupling [4 + 2] annulation of secondary/tertiary anilines with quinazolinones to generate quinoline–spiroquinzolinones. The reaction proceeds smoothly with a relatively broad variety of functional groups, a cheap transition metal catalyst (FeCl3), and environmentally friendly oxidant (H2O2/O2) under mild reaction conditions. Creatively, N-methylanilines
我们报告了一种有效的铁催化交叉脱氢偶联 [4 + 2] 二级/三级苯胺与喹唑啉酮的环化,以生成喹啉-螺喹唑啉酮。在温和的反应条件下,该反应在相对广泛的官能团、廉价的过渡金属催化剂(FeCl 3)和环境友好的氧化剂(H 2 O 2 /O 2)下顺利进行。创造性地,N-甲基苯胺首次用于环加成,因为甲基和亚甲基源都连接到四氢喹啉的 N 原子上。
Expeditious Approach to Indoloquinazolinones via Double Annulations of <i>o</i>-Aminoacetophenones and Isocyanates
作者:Yuxin Ding、Huihui Yan、Rener Chen、Xuqiong Xiao、Zhiming Wang、Lei Wang、Yongmin Ma
DOI:10.1021/acs.joc.0c02155
日期:2021.1.15
A novel procedure for a one-potcascade reaction of o-aminoacetophenones and aryl/aliphatic isocyanates catalyzed/oxidized by the [Pd]/[Ag] system was developed. The reaction involves two C–Nbond and one C–Cbondformations during the double annulation process and the desired indoloquinazolinones and derivatives were afforded up to 81% yields from readily available substrates with a tolerance of a
NHC-Stabilized Gold(I) Complexes: Suitable Catalysts for 6-<i>exo</i>-dig Heterocyclization of 1-(<i>o</i>-Ethynylaryl)ureas
作者:Ana Gimeno、Mercedes Medio-Simón、Carmen Ramírez de Arellano、Gregorio Asensio、Ana B. Cuenca
DOI:10.1021/ol100595s
日期:2010.5.7
3-substituted 1-(o-ethynylaryl)ureas 1 selectively undergo either 6-exo-dig or 5-endo-dig cyclization (to give 4-methylene-3,4-quinazolin-2-ones 2 or indoles 3, respectively) depending on the choice of the metal, ligand, and reaction conditions. The best results (up to 96% yield) in the preparation of the hydroamination products 2 are achieved with the highly bulky NHC-stabilized cationic gold(I) complex