Answer to Question #107079 in Organic Chemistry for Evidence

Question

Treatment of cyclopentane-1,3-dione with a base followed by addition of methyl iodide affords a mixture of 2-methylcyclopentane-1,3-dione, 2,3-dimethylcyclopentane-1,3-dione and 3-methoxy-2-cyclopenten-1-one. Explain with the aid of mechanism how each product is formed

Answer 1

Cyclopentane-1,3-dione + (NaOH + methyl iodide) = 2-methylcyclopentane-1,3-dione + 2,3-dimethylcyclopentane-1,3-dione + 3-methoxy-2-cyclopenten-1-one. 

When a base followed by methyl iodide was added to cyclopentane-1,3-dione one hydrogen was displaced and was replaced by a methyl group.