Zn- and Cu-Catalyzed Coupling of Tertiary Alkyl Bromides and Oxalates to Forge Challenging C-O, C-S, and C-N Bonds.

We describe here the facile construction of sterically hindered tertiary alkyl ethers and thioethers via the Zn(OTf)2-catalyzed coupling of alcohols/phenols with unactivated tertiary alkyl bromides and the Cu(OTf)2-catalyzed thiolation of unactivated tertiary alkyl oxalates with thiols. The present protocol represents one of the most effective unactivated tertiary C(sp3)-heteroatom bond-forming conditions via readily accessible Lewis acid catalysis that is surprisingly less developed.