We present here our results on the preparation of 2-alkynylbenzyl selenide and sulfide derivatives via Sonogashira cross-coupling of benzyl chalcogenides with different alkynes. This cross-coupling reaction proceeded cleanly under mild conditions and was performed with propargyl alcohol as well as alkyl- and arylalkynes. Subsequent electrophilic-cyclization reaction of the 2-alkynylbenzyl selenide and sulfide derivatives using iodine as an electrophilic source gave 4-iodo-3-substituted 1H-isoselenochromenes and -isothiochromenes in moderate yields. The unique product obtained during the course of this cyclization contained a six-membered ring which was confirmed by X-ray diffraction analysis.
我们在此介绍通过苄基卤化物与不同炔烃的 Sonogashira 交联反应制备 2-炔苄基硒化物和硫化物衍生物的研究成果。这种交叉偶联反应在温和的条件下进行,并可与丙炔醇以及烷基和芳基炔进行反应。以碘为亲电源,2-炔苄基硒化物和硫化衍生物随后发生亲电环化反应,以中等产率得到了 4-碘-3-取代的 1H-异硒二苯并二氢吡喃和异二苯并二氢吡喃。这种环化过程中得到的独特产物含有一个六元环,并通过 X 射线衍射分析得到了证实。