5-TERT-BUTYL-2-HYDROXY-BENZALDEHYDE

Hexamethylenetetramine (4.77 g, 34.0 mmol) and 4-tert-Butylphenol (2.55 g, 17.0 mmol) were dissolved in anhydrous trifluoroacetic acid (30 mL) under N2. The reaction mixture wasrefluxed at 80 °C for 24 h. The mixture was poured into 4 M HCl(100 mL) and stirred for 10 min, after which it was extracted with CH2Cl2 (2 × 100 mL). The combined organic layers were washed with 4M HCl (2 × 100 mL) and water (100 mL), then dried over anhydrous Na2SO4 and concentrated under vacuum. The crude product was purifiedby column chromatography, eluting with CH2Cl2 to afford yellow viscous liquid (1.85 g, 61.06percent).4-tert-butyl phenol (10.1 g) was put into a mixture of paraformaldehyde (13 g), tnethylamine (35 mL), magnesium chloride (9.5 g) and acetonitrile (300 mL), followed by stirring at 55°C for 3 hours. 2N hydrochloric acid aqueous solution was put into the reaction mixture to terminate the reaction and the aqueous solution layer was extracted with dichloromethane three times. An organic layer was separated and dried over magnesium sulfate, followed by filtration, and a solvent was removed by distillation under reduced pressure to obtain salicylaldehyde 2 (11.7 g). Paraformaldehyde (1.1 g) and morpholine (1.5 mL) were dissolved in acetonitrile (84 mL) and the prepared salicylaldehyde (3.0 g) and triethylamine (2.8 mL) were put thereinto, followed by stirring at 80°C for 12 hours. A saturated ammonium chloride aqueous solution was put thereinto to terminate the reaction, and the reactant was extracted with dichloromethane three times. An organic layer was separated and dried over magnesium sulfate, followed by filtration and distillation under reduced pressure to obtain salicylaldehyde 3 containing morpholine (4.7 g). Prepared salicylaldehyde (4.7 g) and 1, 2-trans-diaminocyclohexane (1.0 mL) were dissolved in ethanol (84 mL), followed by stirring at room temperature for 3 hours. After distillation under reduced pressure, the obtained reactant was recrystallized in a mixed solvent of n-hexane and dichloromethane to obtain a symmetrical salen derivative 4 (8.7 g). The prepared symmetrical salen derivative (1.5 g) was put into a round bottom flask wrapped with aluminum foil and was dissolved into acetonitrile (47 mL) and then iodomethane (0.4 mL) was put thereinto, followed by stirring at room temperature for 1 day. After removing a solvent by distillation under reduced pressure, the reactant was dissolved in ethanol (80 mL) again and silver nitrate (883 mg) was put thereinto, followed by stirring at 70°C for 1.5 hours. The reaction solution was filtered and distilled under reduced pressure to obtain a symmetrical salen ligand 5 containing ammonium salt (2.0 g). The prepared ligand (2.0 g) was dissolved in methanol (48 mL), and cobalt acetate tetrahydrate (673 mg) was put thereinto, followed by stirring at room temperature for 12 hours, and then lithium chloride (305 mg) was put thereinto and the reactant was oxidized by air. The obtained metal complex was dissolved in dichloromethane again and an organic layer was extracted with water to remove impurities. After distillation under reduced pressure, a symmetrical cobalt-salen catalyst 6 containing ammonium salt (1.3 g) was obtained. Result obtained by spectroscopy experiment of the symmetrical salen ligand containing ammonium salt was as follows.To a three-neck flask, equipped with a reflux condenser, thermometer, a nitrogensource, and magnetic stirrer, was added paratertbutylphenol(16 mmol), sodium hydroxide (100 mmol), distilled water (40 mL), and chloroform (7.0 mL). Themixture was heated to reflux for 8 h. After cooling, thereaction mixture was acidified to pH 2–3 with 2 Mhydrochloric acid, and extracted with ethyl acetate. Thereaction was monitored by TLC. The ethyl acetateextract was treated with vacuum distillation, to givecrude 5-tertbutylsalicylaldehyde. The crude productwas purified by column chromatography gave brownoily liquid product (1.183 g, 42.5percent).

Molecular Weight:178.23
XLogP3:3.3
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:2
Exact Mass:178.099379685
Monoisotopic Mass:178.099379685
Topological Polar Surface Area:37.3
Heavy Atom Count:13
Complexity:181
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes