Suzuki Cross-Coupling Reaction of Sterically Hindered Aryl Boronates with 3-Iodo-4-methoxybenzoic Acid Methylester

The cross-coupling reaction of 3-iodo-4-methoxybenzoic acid methylester with sterically hindered arylboronic esters and especially 5,5-dimethyl-2-mesityl-1,3,2-dioxaborinane, is reported. The optimisation of the process in order to obtain biaryls in good yield by using anhydrous benzene at reflux and sodium phenoxide in the presence of 0.06 equiv. of Pd(PPh3)4 is described.