(1) a carbonyl compound with a hydrogen atom
on its alpha-carbon never equilibrates with its corresponding enol.
(2) a carbonyl compound with a hydrogen atom on its alpha-carbon rapidly equilibrates with its corresponding enol and this process is known as aldehyde-ketone equilibration.
(3) a carbonyl compound with a hydrogen atom on its alpha-carbon rapidly equilibrates with its corresponding enol and this process is known as carbonylation.
(4) A a carbonyl compound with a hydrogen atom on its alpha-carbon rapidly equilibrates its corresponding enol and this process known as keto-enol
Answer: (2)
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