SnCl 4 -mediated oxidative biaryl coupling reaction of 1-naphthol and subsequent ring closure of 2,2′-binaphthol to the dinaphthofuran framework
作者:Tetsuya Takeya、Hirohisa Doi、Tokutaro Ogata、Tsuyoshi Otsuka、Iwao Okamoto、Eiichi Kotani
DOI:10.1016/j.tet.2004.05.077
日期:2004.7
A simple method for the direct synthesis of 2,2′-binaphthols 2 and dinaphtho[1,2-b;2′,1′-d]furans 3 under mild conditions was developed, utilizing a biaryl coupling reaction via electron donor–acceptor complexes of 1-naphthols with SnCl4. Heating of the complex in a sealed tube for (18–24 h) afforded the corresponding o–o coupled product 2 in excellent yield. Prolonged reaction (56–65 h) under the
利用电子供体-受体的联芳基偶联反应,开发了一种在温和条件下直接合成2,2'-联萘酚2和二萘并[1,2- b ; 2',1'- d ]呋喃3的简单方法1-萘酚与SnCl 4的配合物。该复合物在密封管中加热(18-24小时),得到相应的ö - ö偶联产物2的优良率。在相同条件下长时间反应(56–65小时)一步即可获得3的高收率。我们还发现,对于在C-1位上没有羟基以外的取代基的α-萘酚,区域选择性o –o进行了偶联反应。产物2a,2b和2g应该用作天然存在的3,3′-双juglone,3,3′-biplumbagin和艾力汀的合成中间体。