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E1 mechanism and carbocation rearrangement

37 questions on E1 mechanism and carbocation rearrangement from the Organic Reaction Mechanisms IV: Elimination chapter: 8 NEET level, 17 JEE Main, 12 JEE Advanced. Each one opens with its answer and solution.

Practice this topic All Organic Reaction Mechanisms IV: Elimination topics

For the E1 dehydrohalogenation of 2-chloro-2-methylpropane in ethanol (no added strong base), the rate law is NEET level
Which of the following alkyl bromides undergoes E1 elimination (and ionisation) most readily? NEET level
In the E1 mechanism, the slowest (rate-determining) step is NEET level
2-Bromo-2-methylbutane is warmed in ethanol with no strong base present. The major alkene formed is NEET level
3-Methylbutan-2-ol is heated with concentrated H2SO4 at 440 K. The major alkene is JEE Main level
The rate of the E1 (ionisation) reaction of 2-chloro-2-methylpropane is expected to be highest in which solvent? JEE Main level
Which order of the rate of E1 elimination in ethanol is correct for the tertiary halides (CH3)3C-X? JEE Main level
2-Bromo-3-methylbutane is heated in ethanol and reacts only by E1 (SN1 products are ignored). Assume every carbocation that can form does so and that alkene for... JEE Main level
A tertiary alkyl bromide reacts in ethanol with no added base. Replacing every beta-hydrogen by deuterium changes the overall rate of consumption of the bromide... JEE Main level
Which of the following alcohols is dehydrated most easily by warm dilute acid-catalysed E1 dehydration (same acid, same temperature)? JEE Main level
Which of the following statements about the E1 elimination of an alkyl halide is/are correct? JEE Main level
2,2-Dimethylcyclohexanol is heated with concentrated H3PO4. The major alkene and the key step leading to it are JEE Advanced level
1-Cyclobutylethanol, CH3-CH(OH)-C4H7 (cyclobutyl ring attached at the carbinol carbon), is heated with concentrated H2SO4. The major alkene is JEE Advanced level
3-Bromo-3-methylpentane is heated in ethanol (E1 only). The alkene formed in the greatest amount is JEE Advanced level
Which of the following is/are correct for the heating of 2,2-dimethylpropan-1-ol (neopentyl alcohol) with concentrated H2SO4? JEE Advanced level
Heated with concentrated H3PO4, the major alkene from which of these alcohols is formed from a carbocation that has undergone a 1,2-shift? JEE Advanced level
Tert-butyl bromide solvolyses in ethanol at 25 degC to give mainly ethyl tert-butyl ether (SN1) and some 2-methylpropene (E1), both from the same carbocation. W... JEE Advanced level
Match each alcohol in List I with its major alkene from heating with concentrated H3PO4 (List II). List I: P = 3-methylbutan-2-ol; Q = 2-methylpropan-2-ol; R = ... JEE Advanced level
For an E1 elimination of an alkyl halide RX, the rate law is NEET level
Which of the following halides undergoes E1 elimination fastest when heated in ethanol without any added strong base? NEET level
2-Methylbutan-2-ol is heated with conc. H2SO4 at 440 K. The major alkene formed is NEET level
In the E1 mechanism, the rate-determining step is NEET level
3-Methylbutan-2-ol is heated with conc. H2SO4. The major alkene formed is JEE Main level
2,2-Dimethylpropan-1-ol (neopentyl alcohol) is heated with conc. H2SO4. The major alkene formed is JEE Main level
2,2-Dimethylcyclohexan-1-ol is heated with conc. H3PO4. The major alkene formed is JEE Main level
The relative rates of E1 elimination (together with SN1) of tert-butyl halides in ethanol follow the order JEE Main level
2-Bromo-2-methylbutane is warmed in ethanol with no added base. Which statements are correct? JEE Main level
3-Bromo-3-methylhexane, CH3CH2-C(CH3)(Br)-CH2CH2CH3, undergoes E1 elimination. Assume no carbocation rearrangement occurs. How many distinct alkenes can be form... JEE Main level
Which of the following alcohols is dehydrated fastest by warm dilute H2SO4? JEE Main level
The E1 solvolysis of a tertiary alkyl bromide is fastest in which of the following solvents? JEE Main level
2-Methylcyclohexan-1-ol is heated with conc. H3PO4. The major alkene is JEE Main level
Assertion (A): E1 elimination of 2-bromo-2-methylbutane shows no significant primary deuterium kinetic isotope effect on the rate when the beta-hydrogens are re... JEE Main level
2-Bromo-3-methylbutane is heated in ethanol with no added base. Which statements are correct? JEE Advanced level
3,3-Dimethylbutan-2-ol is heated with conc. H2SO4. Which statements are correct? JEE Advanced level
Pinacol, (CH3)2C(OH)-C(OH)(CH3)2, is warmed with dilute H2SO4. The main organic product is JEE Advanced level
A tertiary alkyl bromide reacts in aqueous ethanol at 50 degC by a first-order process with half-life 3.0 h. Product analysis shows that 24% of the substrate co... JEE Advanced level
Each alcohol below is heated with conc. H2SO4 under E1-type conditions that allow 1,2-shifts. For which are 2-methylbut-2-ene the major alkene? JEE Advanced level