Binuclear palladium(I) and platinum(I) dimers stabilized by aromatic ligands: synthesis, structural characterization and reactivity with carbon monoxide

Reaction of PdCl2 with excess of GaCl3 in aromatic solvents leads to binuclear compounds of the general formula [Pd2X2(arene)2], where arene=C6H6, X−=Ga2Cl7 − (1); arene=C7H8, X−=GaCl4 − (2). The solid-state structures of compounds 1 and 2 have been determined by X-ray crystallography. Two molecules of the arene are bound to the dipalladium unit. The compounds 1 and 2 do not react with triphenyl phosphine. Reaction of carbon monoxide with 1 in benzene solution yields [Pd2(GaCl4)2(C6H6)2] (3), for which the crystal structure has also been determined. The compound [Pt2(GaCl4)2(C10H10)2]·2C6H6 (4), which was obtained by reaction of K2[PtCl4] with GaCl3 and naphthalene in a benzene solution, has a similar structure in the solid state.