1. Monsanto Acetic Acid Process Giana Storck, Chemistry, Elmhurst College
In this molecular orbital diagram the CO is donating electrons to the Rh.
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Some History
Acetic acid is an industrially important chemical
During the 19th century, ethanol fermentation was used to make the chemical
Then came an acetaldehyde route to acetic acid (using mercury as a catalyst)
Methanol became an attractive raw material due to its relatively low price
In 1970, Monsanto used this process
Oxidative Addition
CH3I
CH3I
CH3COI
H2O
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CH3OH
CH3CO2H
CO insertion = alkyl migration
Reaction Conditions
10-3 M Rh
180˚ C
30-40 atm
>99% selectivity on methanol
No hydrogen affect
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The rhodium used for this reaction is used in a circular fashion, it can be reused.
Coordination of CO
H2O
Reductive elimination
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