2-Methylcyclohexanol is heated with conc. H3PO4. The major alkene is:

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JEE Main levelSingle correct optionDifficulty 2 of 3o4198

2-Methylcyclohexanol is heated with conc. $H X_{3} PO X_{4}$ . The major alkene is:

A1-methylcyclohexene
B3-methylcyclohexene
Cmethylenecyclohexane
D2-methylcyclohexanone

Answer: A

Acid-catalysed dehydration of a secondary alcohol proceeds by a carbocation (E1) and follows Saytzeff's rule. Loss of the proton from C2 (which carries the methyl group) gives the trisubstituted alkene 1-methylcyclohexene as the major product.

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Answer: A

More questions on Dehydration of alcohols and dehydrohalogenation

2-Methylcyclohexanol is heated with conc. $H X_{3} PO X_{4}$ . The major alkene is: