Chemistry · Hydrocarbons
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Which one of the following will not undergo dehydrogenation?
- A
COCH3
- B
(CH 3)2 CHOH
- C
(CH3)3COH
- D
CH3CH2OH
To undergo dehydrogenation, the compound must have OH group. Only compound in option A is not an alcohol thus, it is the correct answer.
a) COCH3: This option suggests that COCH3 will not undergo dehydrogenation. The chemical formula COCH3 represents acetone, which is a ketone. Ketones do not undergo dehydrogenation reactions because they lack hydrogen atoms attached to the carbon atoms adjacent to the carbonyl group (C=O). Dehydrogenation involves the removal of hydrogen atoms from a molecule, and in ketones, there are no α-hydrogens (hydrogens attached to carbon atoms adjacent to the carbonyl group) available for removal.
b) (CH3)2CHOH: This option states that (CH3)2CHOH will undergo dehydrogenation. The chemical formula (CH3)2CHOH represents isopropanol, also known as 2-propanol. Isopropanol is a secondary alcohol, and it can undergo dehydrogenation under suitable conditions, resulting in the formation of acetone (COCH3). The α-hydrogen on the carbon adjacent to the hydroxyl group (OH) in isopropanol can be removed during dehydrogenation.
c) (CH3)3COH: This option suggests that (CH3)3COH will not undergo dehydrogenation. The chemical formula (CH3)3COH represents tert-butanol, also known as 2-methyl-2-propanol. Tert-butanol is a tertiary alcohol, and tertiary alcohols do not undergo dehydrogenation because they lack α-hydrogens.
d) CH3CH2OH: This option states that CH3CH2OH will undergo dehydrogenation. The chemical formula CH3CH2OH represents ethanol. Ethanol is a primary alcohol, and it can undergo dehydrogenation under suitable conditions, forming acetaldehyde (CH3CHO) as an intermediate.
Tagged under Chemistry · Hydrocarbons · 2013