I need help with this systhesis problem
1-propyne ----> 1.) 1 equivalent of NaNH2 2.)CH3CH2Br 3.) H2 Lindlar Catalyst 4.) HCl 5.)NaN3
To help you with this synthesis problem, let's break it down step by step:
1. Starting with 1-propyne, we want to convert it to the desired product using a series of reactions.
2. The first step involves using 1 equivalent of NaNH2 (sodium amide). Sodium amide is a strong base that can eliminate a hydrogen from the triple bond of 1-propyne, resulting in the formation of a new double bond.
3. Next, we introduce CH3CH2Br (ethyl bromide) into the reaction mixture. Ethyl bromide is an alkyl halide that can undergo nucleophilic substitution reactions. In this case, the nucleophile is the negatively charged carbon atom resulting from the previous step. The ethyl bromide will react with this nucleophile, replacing the bromine atom and forming a new carbon-carbon bond.
4. In the third step, we use a catalyst called the Lindlar catalyst. The Lindlar catalyst is a hydrogenation catalyst that selectively reduces alkynes to form cis-alkenes. The triple bond in the previous product is converted into a double bond, and the hydrogenation is stopped at the cis position by the presence of the Lindlar catalyst.
5. The fourth step involves introducing HCl (hydrochloric acid) into the reaction mixture. HCl is a strong acid, capable of protonating any remaining nucleophile. This protonation prevents further reaction or side reactions from occurring.
6. Lastly, we use NaN3 (sodium azide) in the fifth step. NaN3 is a reagent that can be used to convert alkyl halides into alkyl azides via nucleophilic substitution. In this case, it will react with the ethyl chloride from the previous step, replacing the chlorine atom with an azide group (-N3).
By following these five steps, you can successfully convert 1-propyne to the desired product. However, it's essential to note that each step may require specific reaction conditions, such as temperature, solvent, and reaction time. It's also crucial to pay attention to the stoichiometry of each reagent to ensure the correct amount is used in each step.