O afforded primary selenocarboxylic amides. The cyclization of these compounds with α-halo ketones afforded a variety of functionalized 1,3-selenazoles. Theuse of P 2 Se 5 also allowed the convenient synthesis of selenocarboxylic diamides which were transformed into bis(selenazol-2-yl)alkanes ('bis-selenazoles'). A practical method for the synthesis of selenourea was developed. This useful small building
在 EtOH-H 2 O 存在下腈与 P 2 Se 5 的反应得到伯硒代羧酸酰胺。这些化合物与 α-卤代酮的环化得到了多种功能化的 1,3-硒唑。使用 P 2 Se 5 还可以方便地合成硒代羧酸二酰胺,该二酰胺被转化为双(硒唑-2-基)烷烃(“双硒唑”)。开发了一种合成硒脲的实用方法。这种有用的小结构单元成功地应用于伯2-氨基-1,3-硒唑的合成。
Hypervalent Iodine in Synthesis 53: Synthesis of 2,4-Disubstituted and 2,4,5-Trisubstituted 1,3-Selenazoles
作者:Peng-Fei Zhang、Zhen-Chu Chen
DOI:10.1055/s-2000-6407
日期:——
α-Tosyloxylation of ketones with [hydroxy(tosyloxy)iodo]benzene, followed by treatment with primary selenoamides provides a convenient method of synthesis of selenazoles without the use of lachrymatory and toxic α-haloketones. The synthetic method is simple, mild and the yields are higher.
Novel Conversion of Selenium-containing Five-membered Aromatics to Nitrogen-containing Six-membered Aromatics via Hetero Diels–Alder Reaction with Acetylenic Dienophiles
Treatment of selenium-containing five-membered heteroaromatics with acetylenic dienophiles afforded several nitrogen heterocycles in good to moderate yields by using thermal reaction conditions. These reactions were thought to proceed through sequential [4+2] cycloaddition-selenium extrusion pathway.