Vishwakarma, J. N.; Chowdhury, B. K. Roy; Ila, H., Indian Journal of Chemistry - Section B Organic and Medicinal Chemistry, 1985, vol. 24, p. 472 - 476
Facile Synthesis of 4-Alkyl (and Aryl)-2-aryl-6-diazo-4H- thieno[3,2-b]pyridine-5,7-diones
摘要:
Treatment of 3-{3-alkyl (and aryl)amino-5-arylthieno-2-yl}-2-diazo-3-oxopropanoates 8 with TMSOTf (3 equiv) in the presence of Et3N (6 equiv) in CH2Cl2 for 1 h at room temperature afforded 4-alkyl (and aryl)-2-aryl-6-diazo-4H-thieno[3,2-b]pyridine-5,7-diones 14 in excellent yields. On heating of 14 in the presence of a catalytic amount of Rh-2(CF3CF2CF2CO2)(4) in PhH for 4-10 h at reflux, corresponding ring contraction products, 4-alkyl (and aryl)-5,6-dihydro-4H-thieno[3,2-b]pyrrol-5-ones 16, were produced in good to excellent yields.
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。
Heterocyclization of 3-(R-amino)-3-methylthio-1-phenylpropenones and 5-benzoyl-6-methylthio-1,2-dihydropyridin-2-ones with 1,2- and 1,3-dinucleophilic reagents
作者:V. N. Britsun、N. V. Pikun、A. B. Ryabitskii、M. O. Lozinskii
DOI:10.1007/s10593-011-0862-5
日期:2011.11
The interaction of 3-(R-amino)-3-methylthio-1-phenylpropenones and 1-alkyl-5-benzoyl-3-ethoxycarbonyl-6-methylthio-1,2-dihydropyridin-2-ones with N,N- and N, C-1,2- and 1,3-dinucleophiles proceeded regioselectively by [3+2] and [3+3] cyclocondensation with the formation of derivatives of pyrazole, benzimidazo[1,2-a]-pyridine, benzimidazo[1,2-a] pyrimidine, imidazo[1,2-a] pyrimidine, [1,2,4] triazolo[4,3-b]pyridazine, and 6,7-dihydro-2H-pyrazolo[3,4-b]pyridine. The regioselectivity of the reactions carried out was analyzed.