Preparation of Quaternary Centers via Nickel-Catalyzed Suzuki-Miyaura Cross-Coupling of Tertiary Sulfones.

We describe the development of a nickel-catalyzed Suzuki-Miyaura cross-coupling of tertiary benzylic and allylic sulfones with arylboroxines. A variety of tertiary sulfones, which can easily be prepared via a deprotonation-alkylation route, were reacted to afford symmetric and unsymmetric quaternary products in good yields. We highlight the use of either BrettPhos or Doyle's phosphines as effective ligands for these challenging desulfonative coupling reactions. The utility of this methodology was demonstrated in the concise synthesis of a vitamin D receptor modulator analogue.