Microwave-assisted Kumada-type cross-coupling reactions of iodinated carba-closo-dodecaborate anions.

The microwave-assisted Pd-catalyzed Kumada-type cross-coupling reaction of iodinated carba-closo-dodecaborate anions requires smaller amounts of Grignard reagent and catalyst and results in higher yields in much shorter reaction times in comparison to a reaction with conventional heat transfer. 12-Ph(3)P-closo-1-CB(11)H(11) was identified as the side product of the cross-coupling reactions that use [PdCl(2)(PPh(3))(2)]. The inner salt, which is the first example for a {closo-1-CB(11)} cluster with a B-P bond, was selectively synthesized via a related microwave-assisted cross-coupling protocol and characterized by NMR spectroscopy, elemental analysis, and single-crystal X-ray diffraction. In addition, the crystal structures of the tetraethyl ammonium salts of 12-Ph-closo-1-CB(11)H(11), 12-(4-MeOC(6)H(4))-closo-1-CB(11)H(11), and 12-(H(2)C═(Me)CC≡C)-closo-1-CB(11)H(11) are described.