三溴化金催化端炔与二芳基二硒醚反应合成炔基硒醚

Synthesis of Alkynyl Selenides by Gold Tribromide Catalyzed Reaction of Terminal Alkynes with Diaryl Diselenides

炔基硒醚是合成一些有机硒化合物的重要起始物。本文研究发现,在三溴化金(Au Br3)催化下,端位炔和二芳基二硒醚在弱碱(如碳酸钾)存在下反应,生成炔基芳基硒醚,产率为69%~98%;在空气参与下,于80℃下进行反应,反应条件简单,且二硒醚的两个硒原子均可以被利用。二甲基亚砜(DMSO)是合适的溶剂,在极性较小的溶剂(如甲苯、四氢呋喃)中,此反应不能进行。芳基炔(如苯乙炔、对甲基苯乙炔、对氯苯乙炔等)、烯基炔(如环己烯乙炔)和烷基炔(如1-壬炔)均能顺利进行此反应。当芳基炔苯环的间位或邻位连有取代基时,反应产率较低(69%~82%),而对位无论是连有吸电子基还是给电子基,该反应均可以得到很高的产率(95%)。

Alkynyl selenides are important starting materials for the synthesis of some organic selenides. In this paper,alkynyl selenides were synthesized by the reaction between terminal alkynes and diaryl diselenides catalyzed by gold tribromide（ Au Br3） in the presence of a base such as potassium carbonate in good to excellent yields（ 69% - 98%）. The reaction was performed at 80 ℃ in air,and all the selenium atoms of diaryl diselenides could be taken into use. Dimethyl sulfoxide is a proper solvent. The reaction does not occur when less polar tetrahydrofuran or toluene is used as the solvent. Aryl,alkenyl and alkyl alkynes can smoothly react with diaryl diselenides under the above conditions. Para-substituted phenylacetylene（ such as4-ethynyltoluene,1-ethynyl-4-methoxybenzene,4-fluorophenylacetylene,4-chlorophenylacetylene,etc.） gives rise to alkynyl selenides in good to excellent yields（ 78% - 98%） whether the substituents are electron-donating or-withdrawing. Ortho-and meta-substituted phenylacetylene leads to relatively low yields（ 69% - 82%）.Non-aryl alkynes（ such as 1-nonyne and 1-ethynylcyclohexene） also afford corresponding alkynyl selenides with high yields（ 95%）.