Chapter 22 Multiple Choice Questions

. Which is an unlikely product of the following hydrochlorination of an alkene?

. Which of cations (a)-(d) is the least likely to be an intermediate in the following rearrangement reaction?

. Which cation is not involved in the following rearrangement of an epoxide?

. Which carbonyl compound is the main product of the following reaction of a diol?

. Which carbonyl compound is the main product of the following reaction of a tosylate?

. Which is the main final product of the following diazotization of an amine?

. Which is the main product of the following reaction of an amide?

CH₃CH₂CH₂NH₂

CH₃CH₂NH₂

. Which of the following equations shows an unlikely main product?

. Which lactam would be the main product of the following rearrangement of an oxime when the cis-trans isomerization of the oxime is retarded?

. Which of the following statements is wrong?

Tertiary alkyl groups generally undergo 1,2-shifts to the electron-deficient centres more readily than primary and secondary alkyl groups do.

The bond breaking and making are concerted in the 1,2-shift of a methyl group in carbenium ions.

The transition structure for a 1,2-shift to an electron-deficient centre is regarded as a cyclic three-centre two-electron system.

The configuration of a carbon centre undergoing a 1,2-shift in a carbenium ion is not retained.

. Which alkene is the main product of acid-catalysed dehydration of the following alcohol? The reaction may involve a rearrangement.

. Which is the main product of the following rearrangement of a bicyclic diol?

. The following diol (1) and bromo alcohol (2) could possibly give carbonyl compound(s), A and/or B, by the indicated reactions. Which are the expected results?

Both 1 and 2 give mainly A.

Both 1 and 2 give mainly B.

Diol 1 gives A but 2 gives B as the main product.

Diol 1 gives B but 2 gives A as the main product.

. Diazotization of 1-aminomethyl-3-methylcyclopentanol may give 3-methyl- and 4-methylcyclohexanones as shown below. We represent the rebonding during the formation of 4-methylcyclohexanone as [1,2 ? 1,2]; this indicates that when the C1-C2 bond of the cyclopentanol is broken, the C1-C2 bond of the cyclohexanone is formed. How, in the same way, would we represent the bond breaking and making in the formation of the 3-methylcyclohexanone?