## Step 1: Formation of Nitrosyl Cation (NO⁺) **Explanation:** When sodium nitrite (NaNO₂) and hydrochloric acid (HCl) are mixed, they react to produce nitrous acid (HNO₂), which then forms the **nitrosyl cation (NO⁺)**. This cation acts as an electrophile in the reaction with the amine group of (S)-glutamic acid. **Mechanism Details:** 1. **NaNO₂ + HCl → HNO₂ + NaCl** Sodium nitrite reacts with hydrochloric acid to form nitrous acid. 2. **HNO₂ + HCl → NO⁺ + 2H₂O + Cl⁻** Nitrous acid reacts further with HCl to generate the nitrosyl cation (NO⁺), water, and chloride ion. **Summary:** - **Electrophile generated:** Nitrosyl cation (NO⁺) - **Nucleophile in next step:** Amino group of glutamic acid (NH₂) --- ## Step 2: Reaction of Amino Group with Nitrosyl Cation **Explanation:** The amino group (–NH₂) on (S)-glutamic acid acts as a nucleophile and attacks the nitrosyl cation (NO⁺), resulting in the formation of an N-nitrosamine intermediate. **Mechanism Details:** 1. **Nucleophilic Attack:** The lone pair of electrons on the nitrogen atom of the –NH₂ group attacks the nitrogen atom in NO⁺. 2. **Intermediate Formed:** This leads to the formation of an N-nitrosamine, where the amino group now has an –N=NO group attached. **Arrow-Pushing:** - Arrow from the lone pair on the amino nitrogen to the electrophilic nitrogen of NO⁺. - This creates a bond between the amine nitrogen and the nitrosyl group. --- ## Final Mechanism (so far): 1. **Generation of NO⁺:** NaNO₂ + HCl → HNO₂ → NO⁺ (active electrophile) 2. **Amination Reaction:** (S)-Glutamic acid –NH₂ + NO⁺ → N-nitrosamine intermediate --- ### **Final Answer (for these 2 steps):** - Step 1: **NO⁺ (nitrosyl cation) is generated from NaNO₂ and HCl.** - Step 2: **The amino group of (S)-glutamic acid reacts with NO⁺, forming an N-nitrosamine intermediate.** Let me know if you need the next steps!