Selectfluor-Mediated Tandem Cyclization of Enaminones for the Synthesis of 3-Fluorochromones
作者:Venu Kandula、Pradeep Kumar Thota、Poosa Mallesham、K. Raghavulu、Anindita Chatterjee、Satyanarayana Yennam、Manoranjan Behera
DOI:10.1055/s-0039-1691489
日期:2019.12
An efficient synthesis of various 3-fluorochromones (3-fluoro-4H-chromene-4-ones) fromenaminoketones by using Selectfluor is described. The key step in the synthesis involves tandem fluorination and cyclization to form 3-fluorochromones in good yields. The significant features of this method include simple operational procedures, a high purity of the product, and excellent regioselectivity.
d selenylation/cyclization of enaminones have been realized for the practical synthesis of 3‐selanyl‐4H‐chromen‐4‐ones. This reaction is performed in the mild conditions, no transition metal catalyst or photocatalysts and no additional oxidants are required. In addition, the 3‐selanyl‐4H‐chromen‐4‐ones could be easily converted to selanyl‐functionalized pyrimidines by reacting with benzamidine substrates
已经实现了简单而有效的可见光促进的烯胺酮的硒化/环化反应,可实际合成3-Selanyl-4 H -chromen-4- 。该反应在温和的条件下进行,不需要过渡金属催化剂或光催化剂,也不需要其他的氧化剂。此外,通过与苯甲idine底物反应,可以很容易地将3-selanyl-4 H -chromen-4 -ones转化为selanyl-functionalized嘧啶。
A facile strategy for accessing 3-alkynylchromones through gold-catalyzed alkynylation/cyclization of o-hydroxyarylenaminones
作者:Manjur O. Akram、Saibal Bera、Nitin T. Patil
DOI:10.1039/c6cc07119h
日期:——
A strategy based on tandem alkynylation ofo-hydroxyarylenaminones followed by intramolecular cyclization has been developed to generate a diverse array of 3-alkynyl chromones.
Regioselective copper(I)-catalyzed C–H hydroxylation/C–S coupling: expedient construction of 2-(styrylthio)phenols
作者:Run-Sheng Xu、Lei Yue、Yuan-Jiang Pan
DOI:10.1016/j.tet.2012.04.048
日期:2012.6
Regioselective copper(I)-catalyzed C–H hydroxylation/C–Scoupling of arylthiols with vinyl halides was developed. Starting from substituted arylthiols and vinyl halides, various 2-(styrylthio)phenol derivatives were efficiently prepared. The application of the synthetic methodology to generate the bioactive organic intermediate was also exemplified.
A sequential one-pot, simple and convenient method is described for the synthesis of 3-selenocyanato-4 H -chromen-4-ones by addition, first of DMF-DMA and then of triselenodicyanide as electrophile.