Around 10 Mt per year of acetic acid are manufactured worldwide and 25% of this is produced
Question:
Around 10 Mt per year of acetic acid are manufactured worldwide and ≈25% of this is produced using the CativaTM process. The reaction:
is catalysed by cis-[IrI2(CO)2]−. Methanol is first converted to MeI by reaction with HI, and the catalyst undergoes oxidative addition of MeI to give a fac-A. In the presence of an I− abstractor, substitution of I− for CO leads to fac-B, which undergoes methyl migration. Reaction with I− results in elimination of MeCOI and regeneration of the catalyst.
(a) What is the stereochemistry of cis-[IrI2(CO)2]−?
(b) Show what happens during the oxidative addition of MeI to cis-[IrI2(CO)2]−, and give the structure of fac-A.
(c) Draw the structure of fac-B and describe the mechanism of the methyl migration step.
(d) How does the valence electron count and the oxidation state of the Ir atom change during the catalytic cycle, starting and ending with the catalyst?
Step by Step Answer:
a The stereochemistry of cisIrI2CO2 is octahedral In an octahedral complex there are six ligands surrounding the central metal atom forming a symmetri...View the full answer
