Boron-Oxygen Bond Formation by Palladium-Catalyzed Etheration of 2-Iodo-para-carborane

For the first time, the palladium-catalyzed etheration of 2-iodo-p-carborane with phenolates and alkoxides has been demonstrated. The reactions of 2-iodo-1,12-dicarba-closo-dodecaborane (2-iodo-p-carborane) with sodium salts of phenol, p-cresol, alpha- and beta-napthol, 3-methyl-4-chlorophenol, and 3,4-dimethylphenol using the Pd(dba)(2)/BINAP (dba = dibenzylideneacetone; BINAP = rac-2,2'-bis-(diphenylphosphino)-1,1'-binaphthyl) system in dioxane at 90 degrees C afforded the corresponding 2-p-carboranyl aryl ethers in good to high yields. 2-Methoxy-p-carborane and 2-ethoxy-p-carborane have also been obtained in good yield. The structures of 2-(4-methylphenoxy)-p-carborane and 2-methoxy-p-carborane have been established by X-ray diffraction studies.