We herein described the synthesis of several 3-benzyl-2,5-diarylselenophene derivatives in moderate to good yields using (Z)-benzylselenoenynes as starting material in carbocyclization reactions. The reactions were carried out under mild conditions using only t-BuOK as base, in the complete absence of transition metals or additives. The cyclized 3-benzyl-2,5-diarylselenophenes obtained in the current protocol appear highly promising and attractive intermediates for the synthesis of polysubstituted selenophenes. For instance, 3-benzyl-2,5-diphenylselenophene was treated with Br2 provided the corresponding 3-benzyl-4-bromo-2,5-diphenylselenophene in high yield. 4-Bromoselenophene derivative was applied as substrate in the palladium catalyzed cross-coupling reactions with boronic acids to give the Suzuki type products in excellent yields.
我们在此描述了以(Z)-苯基
硒炔为起始材料,通过碳环化反应合成几种3-苄基-2,5-二芳基
硒烯衍
生物,产率中等到良好。这些反应在温和条件下进行,仅使用t-BuOK作为碱,在完全不使用过渡
金属或添加剂的情况下进行。目前协议获得的环化3-苄基-2,5-二芳基
硒烯显示出极具前景和吸引力的特性,作为多取代
硒烯合成的中间体。例如,将3-苄基-2,5-二苯基
硒烯与Br2反应,得到了相应的3-苄基-4-
溴-2,5-二苯基
硒烯,产率很高。接着,4-
溴硒烯衍
生物作为基质应用于
钯催化的交叉偶联反应,与
硼酸反应生成了优良产率的铃木型产物。