Question

Devise a 5‑step synthesis of the product from the starting material and reagents provided.

Answer 1

The 5-step synthesis involves reactions with various reagents and conditions, including EtMgBr, Pd(PPh3)4, Cu(I) Br, hydrazine, TiCl3, concentrated acetic acid, and TFA/H₂O.

Step-by-step explanation:

The 5-step synthesis of the product from the starting material and reagents provided in Scheme 2 involves the following steps:

1. EtMgBr is added to the starting material in THF at 0°C;
2. 3-tributyltin-2-chloropyridine, Pd(PPh3)4, and Cu(I) Br are added to the reaction mixture in 1,4-dioxane and refluxed;
3. Compound 9 undergoes a two-step reaction: (i) hydrazine at 80°C, followed by (ii) TiCl3;
4. Compound 10 undergoes a reaction with concentrated acetic acid at 110°C;
5. The final step involves treatment of the product with TFA/H₂O (1/1) in THF.