PtCl2 catalysed cascade cyclization of an enediyneâenone system to afford a tetracyclic chromenone is reported, which proceeds through two consecutive highly regioselective 6-endoâdig cyclizations in a single step with the formation of two new CâC bonds and two new rings in excellent yield. A mechanism for this transformation is proposed based on the isolated intermediates.
报道了 PtCl2 催化烯二炔烯酮体系级联环化生成四
环色烯酮的过程,该过程一步完成两个连续的高区域选择性 6-endoâdig 环化,形成两个新的 CâC 键和两个新的环,收率极高。根据分离出的中间产物,提出了这种转化的机理。