Synthesis of electron withdrawing cyclopentadienides as new Lewis acid catalysts

超强酸共轭碱广泛应用于试剂和催化剂中。我们建立了一种以磺酸和四硫杂环戊二烯为原料合成超强酸共轭碱--四氰基环戊二烯的通用方法。为了获得更多的取代基多样性，在环戊二烯环上进行了各种官能化反应，在TBS基团通常为刚性的二氯甲烷-1M盐酸两相体系中，合成的四氰基环戊二烯的加入加速了O-TBS-薄荷醇的水解。

Superacid conjugate bases are widely used in reagents and catalysts. We established a general synthetic method for tetracyanocyclopentadienides, one of superacid conjugate bases, from sulfones and tetracyanothiophene. Various functionalization reactions on a cyclopentadienide ring were performed to give more substituent diversity.The hydrolysis of O-TBS-menthol was accelerated by the addition of synthesized tetracyanocyclopentadienides in dichloromethane-1 M hydrochloric acid biphase system, in which the TBS group was usually rigid.