氯化铯催化硒酚烷基化反应合成不对称硒醚

Cesium Chloride Catalyzed Se-alkylation of Selenol to Synthesize Unsymmetrical Organoselenides

通过卤代烃与硒酚反应合成了不对称硒醚，至少要使用等摩尔的氢氧化铯作碱，与氢氧化钾相比，氯化铯价格昂贵。本文研究用计量的氢氧化钾作催化剂，实验表明，在无水DMF中，4A分子筛存在下，烷基卤、溴代乙酸乙酯、苄基溴及烯丙溴与芳硒酚在室温能有效反应，得到不对称硒醚，收率78％-95％。以苯硒酚（0．1mol）与溴乙烷（0．3mol）反应为例的放大实验，产物苯基乙基硒醚的收率为90．2％。

Preparation of unsymmetrical selenides via the reaction of arylselenol with alkyl halides needs at least equal molar cesium hydroxide as the base. Compared with potassium hydroxide, cesium hydroxide is far more expensive. The paper uses potassium hydroxide as the base and cesium chloride as the catalyst. Thus, in anhydrous DMF, in the presence of 4A molecular sieves, alkyl halides, ethyl bromoacetate, benzyl bromide or allyl bromide reacted with arylselenols to give the corresponding unsymmetrical selenides in 78% -95% yields. The yield of enlargement experiment of the reaction of phenylselenol（0.1 mol） with ethyl bromide（0.3 mol） was 90.2%.