反应详情

To a solution of (4-methylphenyl)(phenyl)methanone (12) (1.9 g, 0.01 mol) in methanol was added 4-methoxybenzyl hydrazine (4.5 g, 0.035 mol) and acetic acid (0.5 mL). The mixture was reflux for 2 h. After cooling, the mixture was concentrated and the residue was extracted with CHCl3, washed with dil. HCl, followed by water, dried over MgSO4 and concentrated in vacuo, to give (Z)-(4-methylphenyl)(phenyl)methanone (4-methoxybenzyl)hydrazone (13). Next, a solution of above benzylhydrazone was dissolved in CH2Cl2 (50 ml) was added dropwise to a solution of Pb(OAC)4 (14.1 g, 0.03 mol) in CH2Cl2 (200 mL). After addition was completed, the mixture was reacted at 30±2° C. for 30 min, the BF3.Et2O (containing 47% of BF3 61 mL) was added. The mixture was reflux for 30 min before quenched into ice water. The organic layer was washed with water, dried over MgSO4 and evaporated. The residue was purified by column chromatography (silica gel-toluene) produce compound 24 (0.6 g). This product was confirmed by comparison of its IR and NMR spectra with that of a sample from the method A.

1. temperatureThe mixture was reflux for 2 h
2. temperatureAfter cooling
3. concentrationthe mixture was concentrated
4. extractionthe residue was extracted with CHCl3
5. washwashed with dil. HCl
6. dry with materialdried over MgSO4
7. concentrationconcentrated in vacuo