Scheme 4. Scope of the cross-coupling reaction. ^aMicrowave irradiation conditions, 100 °C, 24 h, using 7b and 4-bromoanisole, gave 73% AY, compared to 77% AY for standard conditions (as shown, heating in an oil bath). ^bNo Cu₂O additive. ^cn-Bu₂O solvent, 140 °C.