HYDRODESULFURIZATION OF THIOPHENE AND BENZOTHIOPHENE TO BUTANE AND ETHYLBENZENE BY A HOMOGENEOUS IRIDIUM COMPLEX

Reaction of the dimer [CpIrHCl](2) (Cp* = eta(5)-C5Me5) in benzene so lution with either thiophene or benzothiophene at 90 degrees C in the presence of H-2 gives the hydrogenolysis products [CpIrCl](2)(mu-H)(m u-SC4H9) (1) and [CpIrCl](2)(mu-H)[mu-S(C-6-H-4)CH2CH3] (2), respecti vely, in high yields. Upon further thermolysis under H-2, the complete ly desulfurized products, butane and ethylbenzene, can be made. Comple xes 1 and 2 were characterized by single-crystal X-ray diffraction. In the absence of H-2, reaction of [CpIr HCl](2) with thiophene gives a n additional trinuclear product [CpIrCl](3)(H)(SC4H6) (3), which was also structurally characterized.