Question

In each reaction box, place the best reagent and conditions from the list below.

In each reaction box, place the best reagent and conditions from the list below. In each reaction box, place the best reagent and conditions from the list below.

Answer 1

Concepts and reason

The rearrangement reaction is a type of organic reaction in which the substituents on the reactant molecule rearranges by moving from one carbon atom to another carbon atom using suitable reagents. In general, rearrangements reactions result in the formation of structural isomers. The overall rearranegement reaction occurs through a series of steps such as substitution, elimination, addition etc.

Fundamentals

Tosylation of alcohol: Alcohols are converted to tosylates on reaction with ptoulenesulfonyl chloride and pyridine acts as a base.

Elimination reaction: The chemical reaction in which the elimination of leaving groups takes place to form unsaturated compound.

General elimination reaction is given below:

Examples:

i) Dehydration (removal of ${{\rm{H}}_{\rm{2}}}{\rm{O}}$ ).

ii) Dehydrohalogenation (removal of ${\rm{HX}}$ ).

The reagents used for the elimination reaction is

Anti-Markovnikov’s rule: The negative part of the reagent adds to the less substituted carbon atom of the substrate.

Hydroboration-oxidation: Alkenes are converted to alcohols using the following reagents

${\rm{B}}{{\rm{H}}_{\rm{3}}}{\rm{/THF and }}{{\rm{H}}_{\rm{2}}}{{\rm{O}}_{\rm{2}}}{\rm{,NaOH,}}{{\rm{H}}_{\rm{2}}}{\rm{O}}$ . In this syn-addition, product formation takes place.

The mechanism for the formation of tosylates:

The mechanism of the reaction is

Ans:

The best reagent and conditions for the following reaction is represented below: