[BMim]OH Functionalized Ionic Liquid-Mediated Construction of Ferrocenyl β‑Ketosulfone Derivatives.

The first 1-butyl-3-methylimidazole hydroxide ([BMim]-OH) functionalized ionic liquid-mediated catalytic strategy was proposed for the construction of ferrocenyl β-ketosulfone derivatives. A series of novel ferrocenyl derivatives were synthesized by a facile one-step reaction of chloroacetylferrocene with sodium sulfinates in dichloromethane (DCM) under air and mild conditions. All these synthesized ferrocenyl derivatives were comprehensively characterized using NMR (1H and 13C) spectroscopy as well as HRMS techniques. Compounds 3a, 3d, and 3f were further confirmed using single crystal X-ray diffraction analysis. This catalytic approach provided a straightforward and effective synthetic strategy for the assembly of structurally diverse ferrocenyl β-ketosulfones with high step-economy and exceptional functional group tolerance. The results could facilitate the functionalized application of developing new ferrocenyl β-ketosulfone derivatives.