Visible-Light-Promoted Intramolecular Annulation of 2-Alkynylbiphenyl Compounds to Synthesize 9-Sulfenylphenanthrenes Under Metal-Free and Additive-Free Conditions

Tao Ma, Mixue Bian, Xinxin Lin, Zhao Yang, Xiaobing Yang, Jindian Duan, Ning Zhu, Chengkou Liu, Zheng Fang, Kai Guo