When an alcohol reacts with PX5, the order or reactivity of alcohol is
Correct answer: B. 3° >2° >1°
- A. 1°> 2° >3°
- B. 3° >2° >1°
- C. 2° >1° >3°
- D. Both B and C are correct
Explanation
The reactivity of alcohols with phosphorus pentachloride (PX5, where X is a halogen, usually chlorine) is influenced by the structure of the alcohol. The reaction involves the replacement of the hydroxyl group (-OH) in the alcohol with a halogen atom from PX5, leading to the formation of an alkyl halide. The order of reactivity generally follows the trend: Tertiary Alcohol>Secondary Alcohol>Primary Alcohol Tertiary alcohols are generally more reactive than secondary alcohols, and secondary alcohols are more reactive than primary alcohols in this reaction.
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About Alcohols and Phenols
Alcohols are classified as primary, secondary or tertiary and studied through their hydrogen bonding, acidity, oxidation and reactions with active metals, acids and halogenating agents. Phenols require separate treatment because the hydroxyl group is attached to an aromatic ring, making their acidity and electrophilic substitution different from ordinary alcohols.
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