3,3-Dimethylbutan-2-ol is heated with conc. H2SO4. Select all correct statements.

Loss of water from the protonated alcohol gives a secondary carbocation.

A 1,2-methyl shift converts it to a more stable tertiary carbocation.

The major alkene is 2,3-dimethylbut-2-ene.

Loss of water from the protonated alcohol gives a secondary carbocation.

A 1,2-methyl shift converts it to a more stable tertiary carbocation.

The major alkene is 2,3-dimethylbut-2-ene.

2,3-Dimethylbut-1-ene is the major alkene, as there are more hydrogens available on the methyl groups.

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JEE Advanced levelOne or more correct optionsDifficulty 3 of 3o4109

3,3-Dimethylbutan-2-ol is heated with conc. $H X_{2} SO X_{4}$ . Select all correct statements.

ALoss of water from the protonated alcohol gives a secondary carbocation.
BA 1,2-methyl shift converts it to a more stable tertiary carbocation.
CThe major alkene is 2,3-dimethylbut-2-ene.
D2,3-Dimethylbut-1-ene is the major alkene, as there are more hydrogens available on the methyl groups.

Answer: A, B, C

Protonation and loss of water give the secondary 3,3-dimethylbut-2-yl cation. A methyl group migrates from C-3 to C-2, giving the tertiary 2,3-dimethylbut-2-yl cation. Loss of a proton from C-3 gives the tetrasubstituted alkene 2,3-dimethylbut-2-ene (Saytzeff), so the fourth statement is false.

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3,3-Dimethylbutan-2-ol is heated with conc. HX2​SOX4​. Select all correct statements.

Answer: A, B, C

More questions on Dehydration of alcohols and dehydrohalogenation

3,3-Dimethylbutan-2-ol is heated with conc. $H X_{2} SO X_{4}$ . Select all correct statements.