Yield:-

Reaction Conditions:

in ethanol;Reflux;

Steps:

4.2. General method for synthesis of o-hydroxybenzylamines 1-16 and corresponding urea derivatives 17-32

General procedure: Anilines (4.0 mmol) in ethanol (10 mL) was treated with equimolar quantities of substituted salicylaldehydes. The mixture was refluxed for 4-6 h, and the reaction was monitored by TLC. The products thus precipitated were filtered and recrystallized in ethanol. Without further purification, to an ethanolic solution of synthesized Schiff bases, NaBH₄ (4.0 mmol) was dissolved in ethanol and slowly added in an ice bath with stirring. The mixture was refluxed for 2-3 h. After that, the solvent was evaporated and water (15 mL) was added. The product extraction was carried out with CH₂Cl₂ (3 × 20 mL). The organic layer was dried over anhydrous Na₂SO₄ and concentrated. The residue was purified by recrystallization from ethanol to afford white or yellow crystals (1-16).

References:

Li, Zi-Lin;Li, Qing-Shan;Zhang, Hong-Jia;Hu, Yang;Zhu, Di-Di;Zhu, Hai-Liang [Bioorganic and Medicinal Chemistry,2011,vol. 19,# 15,p. 4413 - 4420] Location in patent:experimental part