1,4-Diols resulting from the double addition of ArCCLi (Ar = Ph, substituted phenyl, 2-thienyl) to ortho-C6H4(CHO)2 undergo cascades to tetracenes on simple admixture of LiHDMS, CS2 and MeI. Acene formation proceeds by [3,3]-sigmatropic rearrangement of xanthate anions followed by 6π electrocyclisations. The reactions are terminated by E2 or anionic Chugaev-type eliminations. Structural packing motifs and electronic properties are reported for the tetracenes.
从ArCCLi(Ar = Ph,取代苯基,2-噻吩基)双加成到ortho-C6H4(CHO)2产生的1,4-二醇,在简单混合LiHDMS、CS2和MeI后发生级联反应生成四环芳烃。芳烃的形成通过黄硫酸酯阴离子的[3,3]-σ迁移重排,然后是6π电环化反应。反应通过E2或阴离子Chugaev型消除终止。报道了四环芳烃的结构堆积模式和电子性质。