catalytic phenylation reaction of α,β‐unsaturated acylazoliums was developed. A combination of N‐heterocyclic carbene and potassium ion cooperatively catalyzed the cyclization of α,β‐unsaturated acylazoliums with phenolates, which are directly generated from α,β‐unsaturated phenolic esters. Mechanistic studies demonstrated that the potassium ion plays a vital role in this reaction.