Allylic C–S Bond Construction through Metal-Free Direct Nitroalkene Sulfonation
journal contributionposted on 22.01.2018, 00:00 by Xue Lei, Lei Zheng, Chuanxin Zhang, Xiaodong Shi, Yunfeng Chen
A metal-free, open-flask protocol was developed for the preparation of allylic sulfones through direct condensation of sodium arylsulfinates and β,β-disubstituted nitroalkenes. The key step of this process was the Lewis base-promoted equilibrium between nitroalkenes and allylic nitro compounds. Through this process, the readily available conjugated nitroalkenes can be easily converted into allylic nitro compounds, which contain more reactive CC bonds toward the sulfonyl radical addition. As a result, allylic sulfones were prepared in excellent yields with a broad substrate scope under mild conditions.