Chemistry - Hydrocarbon Question with Solution | TestHub
In the following reaction sequence, the product is
Options:
Answer:
Solution:
The given reactant is .
When treated with (a strong base), the acidic terminal alkyne proton is abstracted to form an acetylide ion:
This acetylide ion undergoes an intramolecular reaction. The nucleophilic carbon attacks the carbon bearing the bromine atom, displacing the bromide ion. This results in the formation of a 14-membered cyclic alkyne, cyclotetradecyne (Product X).
Next, cyclotetradecyne is treated with in the presence of Lindlar's catalyst. Lindlar's catalyst ( poisoned with lead acetate or quinoline) is used for the partial reduction of alkynes to alkenes. It specifically undergoes syn-addition of hydrogen, converting the alkyne into a cis-alkene.
Therefore, the triple bond in cyclotetradecyne is reduced to a cis double bond, yielding cis-cyclotetradecene as Product Y.
Option (B) correctly represents the structure of cis-cyclotetradecene.
Answer:
