Chemoselective one-pot access to benzo[e]indole-4,5-diones and naphtho[2,1-b]thiophene-4,5-diones via copper-catalyzed oxidative [3 + 2] annulation of α-oxoketene N,S-acetals/β-ketothioamides with α-/β-naphthols
作者:Dhananjay Yadav、Gaurav Shukla、Monish A. Ansari、Abhijeet Srivastava、Maya Shankar Singh
DOI:10.1016/j.tet.2018.08.026
日期:2018.10
An operationally simple and efficient one-pot method for the synthesis of 1-aroyl (or alkanoyl)-2-thioalkyl-3-aryl (or alkyl)-3H-benzo[e]indole-4,5-diones and naphtho[2,1-b]thiophene-4,5-diones has been devised by copper-catalyzed cross-coupling of α-oxoketene N,S-acetals/β-ketothioamides with α-/β-naphthols in open air for the first time. The key to the success of this transformation is the room temperature
一种操作简单有效的一锅法,用于合成1-芳酰基(或烷酰基)-2-硫烷基-3-芳基(或烷基)-3 H-苯并[ e ]吲哚-4,5-二酮和萘并[首次在露天条件下通过铜催化的α-氧杂环丁烯N,S-乙缩醛/β-酮硫酰胺与α-/β-萘酚的交叉偶联反应设计了2,1- b ]噻吩-4,5-二酮。。该转化成功的关键是室温下将α-/β-萘酚氧化为1,2-萘醌作为反应性物质,然后通过α-氧杂环丁烯N,S进行正式的[3 + 2]环化反应-缩醛/β-酮硫酰胺通过迈克尔加成/互变异构化/氧化/环化/芳香化反应的级联序列,使得能够将吡咯/噻吩环加到萘醌部分上。此外,在无溶剂条件下将苯并[ e ]吲哚-4,5-二酮转化为五环稠合的吩嗪衍生物。根据我们的实验结果,提出了该化学选择性方案的初步机理论据,该方案得到了对照实验的充分验证和支持。
In(OTf)<sub>3</sub>-catalysed one-pot versatile pyrrole synthesis through domino annulation of α-oxoketene-N,S-acetals with nitroolefins
作者:Abhijeet Srivastava、Gaurav Shukla、Anugula Nagaraju、Girijesh Kumar Verma、Keshav Raghuvanshi、Raymond C. F. Jones、Maya Shankar Singh
DOI:10.1039/c4ob00781f
日期:——
In(OTf)3-catalyzed robust and sustainable one-pot access to previously unknown and synthetically demanding polysubstituted pyrroles via [3 + 2] annulation of α-oxoketene-N,S-acetals with β-nitrostyrenes has been achieved under solvent-free conditions. The merit of this domino Michael addition/cyclization sequence is highlighted by its operational simplicity, short reaction time (5–10 min), good to
Lewis acid mediated three-component one-flask regioselective synthesis of densely functionalized 4-amino-1,2-dihydropyridines via cascade Knoevenagel/Michael/cyclization sequence
highly convergent and regioselective one-potsynthesis of hitherto unreported 4-amino-1,2-dihydropyridines has been achieved viathree-component domino coupling (3CDC) of α-oxoketene-N,S-arylaminoacetals, aldehydes, and malononitrile in the presence of InCl3 under solvent-free conditions. The merit of this cascade Knoevenagel condensation/Michael addition/cyclization sequence is highlighted by its atom-economy
α-Functionalized ketene N,S-acetals as two-carbon synthons in the reaction with 1,2-naphthoquinone 1-methide. Synthesis of 3-amino-1H-benzo[f]chromenes
作者:Anton V. Lukashenko、Dmitry V. Osipov、Vitaly А. Osyanin、Yuri N. Klimochkin
DOI:10.1007/s10593-020-02694-5
日期:2020.5
1-[(dimethylamino)methyl]naphthalen-2-ol with push-pull ketene N,S-acetals containing an electron-withdrawing group in the α-position. It is assumed that the reaction proceeds as a [4+2] cycloaddition of ketene N,S-acetals to in situ generated 1,2-naphthoquinone 1-methide. Quantum-chemical methods were used to study the synchronicity of the Diels–Alder reaction.
在1-[((二甲基氨基)甲基]萘-2-醇与推挽式乙烯酮N,S-缩醛含有吸电子基团的反应中获得了一系列3-氨基-1H-苯并[ f ]色烯。在α位置。假定反应以烯酮N,S-缩醛的[4 + 2]环加成反应原位产生的1,2-萘醌1-甲基化物进行。量子化学方法用于研究Diels-Alder反应的同步性。
Direct Construction of 2-Aryliminochromenes from Arynes, <i>N</i>,<i>S</i>-Keteneacetals, and DMF
作者:Li-Rong Wen、Ning-Ning Man、Wen-Kui Yuan、Ming Li
DOI:10.1021/acs.joc.6b00843
日期:2016.7.15
A concise and direct synthetic strategy for the construction of 2-aryliminochromene skeleton by cascade three-component coupling reaction of arynes, N,S-keteneacetals, and DMF in good yields has been disclosed. The process demonstrates the first example of aryne chemistry combined with N,S-keteneacetals. Using this strategy, an expeditious synthesis of biologically important arylimino-2H-chromene-3-
已经公开了通过芳烃,N,S-酮缩醛和DMF的级联三组分偶联反应以良好的产率构建2-芳基亚甲基苯胺骨架的简明而直接的合成策略。该方法证明了芳烃化学与N,S-烯酮缩醛结合的第一个例子。使用这种策略,可以快速合成生物学上重要的arilimino-2 H -chromene-3-羧酰胺。