N-phenylbenzamide synthesis by nucleophilic substitution with 1,3-diphenylthiourea

Objective: N-phenylbenzamides are important and biologically active compounds. N-phenylbenzamides have been synthesized by some routes. An attempt has been made to find out the new route to synthesize N-phenylbenzamides. Methods: The reaction was carried out by reacting substituted benzoyl chlorides with 1,3-diphenylthiourea in the presence of triethylamine in THF at 70 °C. After 4hr the product was purified and identified. Results: An excellent and pure yield of N-phenylbenzamides was obtained by reacting substituted benzoyl chlorides with 1,3-diphenylthiourea. The proposed mechanism follows imino alcohol-amide tautomerism and suggests the involvement of rearrangement intermediate. Conclusion: 1,3-diphenylthiourea is inexpensive commodity chemical and it is found to be the useful reagent for the direct conversion to N-phenylbenzamide. The proposed mechanism follows imino alcohol-amide tautomerism and suggests the involvement of rearrangement intermediate. The synthesis gave pure, high yield, and the one and only isolated product.