Aryl coupling reactions are bond-forming transformations in which an aryl fragment is joined to another molecular fragment, most commonly another aryl, alkenyl, alkynyl, alkyl, or heteroatom-bearing partner. The term includes metal-mediated and metal-catalysed processes that couple an aryl electrophile, such as an aryl halide or pseudohalide, with an organometallic or other nucleophilic partner. Their defining feature is construction of a new bond at the aromatic carbon while retaining the aryl framework. Aryl–aryl coupling is the subclass that directly joins two aryl groups ^[1]. Aryl iodides are especially recognised electrophilic substrates for coupling because the carbon–iodine bond can participate in catalytic activation steps ^[2].