Question

Question:Draw the products of the following reaction, where T is tritium:

Short answer

When coenzyme B-12 acts upon the reactant, it gets added with the tritium attached to C₃ and there forms a radical. Now, the C - OH bond breaks and it gets bonded with C₃. Now the radical is formed at C₂. At the same time, the oxidation state of cobalt in B-12 changed to +2. Now the radical at C₂ is substituted with hydrogen in the coenzyme. Then the radical in the carbon in coenzyme is lost and the oxidation number of cobalt is regained. When the molecule is dehydrated, these products are obtained.

Step-by-step solution

Mechanism for the given reaction

When coenzyme B-12 acts upon the reactant, it gets added with the tritium attached to C₃ and there forms a radical. Now, the C - OH bond breaks and it gets bonded with C₃. Now the radical is formed at C₂. At the same time, the oxidation state of cobalt in B-12 changed to +2. Now the radical at C₂ is substituted with hydrogen in the coenzyme. Then the radical in the carbon in coenzyme is lost and the oxidation number of cobalt is regained. When the molecule is dehydrated, these products are obtained.

Step 2: Final product for the reaction

If the amount of coenzyme is limited, the product formed will be changed. The second hydrogen in the coenzyme B-12 will be substituted with tritium. Thus the final product is as shown below: