DABCO‐Mediated C−O Bond Formation from Csp2‐Halogen Bond‐Containing Compounds and Alkyl Alcohols.

An efficient protocol for C−O bond formation from Csp2−X (X=Br, Cl) bond‐containing compounds and alkyl alcohols in the presence of 1,4‐diazabicyclo[2.2.2]octane (DABCO) as catalyst and base under mild conditions is described. The densely functionalized 2(5H)‐furanone products can be generally obtained in moderate to excellent yields via a metal‐free protocol at room temperature without added solvent. Killing two birds with one stone: A C−O bond formation reaction at room temperature in moderate to excellent yields is described. The reaction uses DABCO as both the base and catalyst. [ABSTRACT FROM AUTHOR]