More than two decades elapsed between the development of a homogeneous catalytic process...

More than two decades elapsed between the development of a homogeneous catalytic process for producing acetic acid in the late 1960s and convincing experimental evidence for the key intermediate [CH₃Rh(CO)₂I₃]^- ( Figure 14.20 ). Describe the evidence presented for this intermediate. (A. Haynes, B. E. Mann, D. J. Gulliver, G. E. Morris, P. M. Maitlis, J. Am. Chem. Soc., 1991 , 113 , 8567.)