Methyl 4-Formylbenzoate → 4-[(4-Cyclohexylphenylimino)methyl]benzoic acid methyl ester
Reaction equation
[CH:1]([C:3]1[CH:12]=[CH:11][C:6]([C:7]([O:9][CH3:10])=[O:8])=[CH:5][CH:4]=1)=O.[CH:13]1([C:19]2[CH:25]=[CH:24][C:22]([NH2:23])=[CH:21][CH:20]=2)[CH2:18][CH2:17][CH2:16][CH2:15][CH2:14]1>CO>[CH3:10][O:9][C:7](=[O:8])[C:6]1[CH:11]=[CH:12][C:3]([CH:1]=[N:23][C:22]2[CH:24]=[CH:25][C:19]([CH:13]3[CH2:18][CH2:17][CH2:16][CH2:15][CH2:14]3)=[CH:20][CH:21]=2)=[CH:4][CH:5]=1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
Methyl 4-formylbenzoate (47 g, 285 mmol) was dissolved in methanol (400 ml) and a solution of 4-cyclohexylaniline (50 g, 0.285 mmol) in methanol (200 ml) is slowly added with mechanical stirring. More methanol (1 l) was added and the suspension was stirred at room temperature for 3 days. Filtration, washing and drying in vacuo afforded 90.7 g (99%) of 4-[(4-cyclohexylphenylimino)methyl]benzoic acid methyl ester. This was dissolved in N-methylpyrrolidone (855 ml) and methanol (45 ml). With mechanical stirring sodium borohydride pellets (42.4 g, 1.12 mol) was added in portions keeping the temperature below 40° C. The mixture was then stirred at room temperature for 2 hours and at 40° C. for 16 hours. The mixture was cooled to 5° C. and water (2 I) was slowly added. Then acetone (350 ml) was added and the mixture was stirred at 5° C. for 1 hour. Filtration, washing with water (2×500 ml) and drying in vacuo afforded 78 g (86%) of 4-[(4-cyclohexylphenylamino)-methyl]benzoic acid methyl ester as a solid.