A novel trinuclear copper(I) complex with a chelating tricarbene ligand is shown to be an efficient catalyst for the arylation of different classes of compounds containing N–H or O–H functions. Different kinds of azole rings (pyrazole, imidazole, 1,2,4-triazole) can be arylated with comparable efficiencies at relatively mild temperatures (100 °C). The catalyst activates aryl iodides, bromides and even