Question

2. Using the amount (mols) of benzene (C6H6) produced during the course of a complete transfer hydrogenation reaction, how would you be able to distinguish the following naturally occurring fatty acids from one another? Provide a balanced equation with skeletal structures showing the complete transfer hydrogenation of each acid shown below. Stearidonic acid and linolenic acid: Predict the product(s) and provide a fully balanced chemical equation for each of the following hydrogenation reactions: 3. 10% Pd /C 10% Pd/C На

Answer 1

2)

In transfer hydrogenation reaction, the Hydrogen atoms from 1,3-cyclohexadiene are transferred to the concerned acid. Meanwhile, 1,3-cyclohexadiene is converted to Benzene.

Thus, if there is 'n' alkene double bonds in the acid, then 'n' moles of 1,3-cyclohexadiene are needed and n moles of Benzene are produced.

For, Stearidonic Acid, it will produce 4 moles of Benzene.

OH 0H 0 4 4 Stearidonic Acid Hydrogenation

For Linolenic Acid, it will produce 3 moles of Benzene,

O H H O 3 +3 Linolenic Acid Hydrogenation 1

In general, in case of transfer hydrogenation, moles of benzene produced and moles of 1,3-cyclohexadiene needed equals the number of Carbon-Carbon double bonds.