Synthesis and antidepressant-like activity of selenophenes obtained viairon(iii)–PhSeSePh-mediated cyclization of Z-selenoenynes
作者:Bibiana M. Gai、André L. Stein、Juliano A. Roehrs、Filipe N. Bilheri、Cristina W. Nogueira、Gilson Zeni
DOI:10.1039/c1ob06548c
日期:——
We present here the synthesis and antidepressant-like action of a series of 2,5-disubstituted-3-(organoseleno)-selenophenes prepared by a novel synthetic route, the FeCl3âdiorganyl dichalcogenide-mediated intramolecular cyclization of (Z)-chalcogenoenynes. The cyclized products were obtained in good yields. The results showed that 2c, 2d, 2e and 2o, evaluated in the mouse forced-swimming test, elicited an antidepressant-like activity. The studies clearly show that the phenyl group at the 2-position and an organoselenium group at the 3-position of the selenophene ring are essential for the antidepressant-like activity of selenophenes. A close inspection of the results also revealed that the fluorophenyl portion in the organoselenium group is fundamental for the antidepressant-like action of this class of organochalcogens.
Copper(II)-Mediated Intramolecular Cyclization of (Z)-Chalcogenoenynes: Synthesis of 3-Halochalcogenophene Derivatives
作者:Daniela A. Barancelli、Ricardo F. Schumacher、Marlon R. Leite、Gilson Zeni
DOI:10.1002/ejoc.201100992
日期:2011.11
We present our results on the cyclization of (Z)-chalcogenoenynes mediated by copper(II) salts to afford 3-halochalcogenophenes in satisfactory yields through an intramolecular 5-endo-dig cyclization. The methodology was carried out using CuCl2 at 50 °C or CuBr2 at room temperature under an ambient atmosphere. The reaction took place under very mild reaction conditions and tolerated considerable functionality
我们展示了由铜 (II) 盐介导的 (Z)-硫属元素烯环化的结果,通过分子内 5-endo-dig 环化以令人满意的产率提供 3-卤代硫属元素烯。该方法是在 50 °C 下使用 CuCl2 或在室温下在环境气氛下使用 CuBr2 进行的。该反应在非常温和的反应条件下进行并且耐受相当大的官能度。在钯催化的与硼酸的交叉偶联反应中,将一种 3-溴-硒吩衍生物用作底物,以良好的收率得到 Suzuki 型产物。
Butyltellurium Tribromide: A Suitable Electrophilic Source to Cyclization Reactions
We present here our results of the electrophilic cyclization reaction of (Z)-chalcogenoenynes using butyltellurium tribromide as an electrophilic source. The cyclization reaction proceeded cleanly under mild reaction conditions and 3-(butyltellanyl)chalcogenophenes were formed in moderate to excellent yields. Subsequent, using these heterocycles as substrate to palladium-catalyzed cross-coupling reactions a new carbon-carbon bond was formed in good yields.
Electrophilic Cyclization of (<i>Z</i>)-Selenoenynes: Synthesis and Reactivity of 3-Iodoselenophenes
作者:Diego Alves、Cristiane Luchese、Cristina W. Nogueira、Gilson Zeni
DOI:10.1021/jo070835t
日期:2007.8.31
We present here our results of the electrophilic cyclization reaction of (Z)-selenoenynes with different electrophiles such as I-2, ICl, PhSeBr, and PhSeCl. The cyclization reaction proceeded cleanly under mild reaction conditions, and 3-substituted selenophenes were formed in moderate to excellent yields. We observed that the nature of solvent and structure of (Z)-selenoenyne were important to the cyclization reaction. In addition, the obtained 3-iodoselenophenes were readily transformed to more complex products using a metal-halogen exchange reaction with n-BuLi and trapping the intermediate formed with aldehydes, furnishing the desired secondary alcohols in good yields. Conversely, using the palladium or copper catalyzed cross-coupling reactions with terminal alkynes or alkyl alcohols, we were able to convert 3-iodoselenophene to Sonogashira or Ullmann type products, respectively, in good yields.