Department of Organic Chemistry, School of Chemistry, University of Madras, Guindy Campus, Chennai 600 025, Tamil Nadu, India.
J Org Chem. 2012 Oct 19;77(20):9053-71. doi: 10.1021/jo301410w. Epub 2012 Sep 28.
A ZnBr(2)-mediated regioselective annulation of unsymmetrical 1,2-diarylmethinedipivalates in DCM at room temperature led to the formation of annulated arenes and heteroarenes. The annulation of the dipivalate proceeds through the intermediacy of benzylic carbocations followed by intramolecular cyclization and subsequent aromatization to give the annulated products. The annulation methodology is highly efficient for the syntheses of anthracene as well as naphtho[b]thiophene analogues.
在室温下，二溴化锌（ZnBr(2)）介导的非对称 1,2-二芳基甲叉二苯甲酸盐在二氯甲烷（DCM）中的区域选择性环化反应导致了稠环芳烃和杂环芳烃的形成。二苯甲酸盐的环化反应通过苄基碳正离子中间体进行，随后进行分子内环化和随后的芳构化，得到稠环产物。该环化方法对于蒽以及萘并[b]噻吩类似物的合成非常有效。
