The present disclosure is directed to a traceless directing group in a radical cascade. The chemo- and regioselectivity of the initial attack in skipped oligoalkynes is controlled by a propargyl alkoxy moiety. Radical translocations lead to the boomerang return of radical center to the site of initial attack where it assists to the elimination of the directing functionality via β-scission in the last step of the cascade. In some aspects, the reaction of the present invention is catalyzed by a stannane moiety, which allows further via facile reactions with electrophiles as well as Stille and Suzuki cross-coupling reactions. This selective radical transformation opens a new approach for the controlled transformation of skipped oligoalkynes into polycyclic ribbons of tunable dimensions.
本公开涉及一种在自由基级联中无痕定向基团。跳跃寡
炔烃中的初始攻击的
化学和区域选择性由
丙炔烯氧基团控制。自由基转位导致自由基中心回到初始攻击点的回旋,它在级联的最后一步中通过β-裂解协助消除定向功能。在某些方面,本发明的反应由一种
锡烷基团催化,它允许通过与亲电试剂以及Stille和Suzuki交叉偶联反应的简便反应进一步进行。这种选择性的自由基转化为控制跳跃寡
炔烃转化为可调尺寸的多环
核糖带提供了一种新方法。