Synthesis, resolution, and stabilities of a cationic chromenoxanthene [4]helicene

Org Lett. 2010 Apr 16;12(8):1748-51. doi: 10.1021/ol1003466.

Abstract

1,13-Dimethoxychromenoxanthenium, a key intermediate in the synthesis of the classical trioxatriangulenium cation, was isolated and characterized for the first time. This [4]helicene was resolved through a CSP-HPLC procedure, with chemical and configurational stabilities being determined and compared.