4-Butoxybenzaldehyde

CLEAR YELLOW TO ORANG-RED LIQUID

In a 100 mL roundbottomed flask equipped with a reflux condenser and a magneticstirring bar were dissolved 4-hydroxybenzaldehyde (35 g, 287 mmol) and 1-bromobutane (30.92 mL, 287 mmol) in DMF(750 mL). The mixture then was stirred under nitrogen for 20 min.Anhydrous potassium carbonate (118.83 g, 860 mmol) was thenadded and the mixture was stirred and heated at 70 °C under nitrogen.After 20 h, the reaction was allowed to cool to room temperature, treated with excess water, and extracted with ethylacetate. The combined organic extracts were then washed withwater several times and dried over anhydrous sodium sulfate, filtered. The crude productwas purified by chromatography (PE/EA, 20/1) yielding a brown oil. Yield: 95percent; 1H NMR (500 MHz, CDCl3) δH(ppm): 9.89 (s, 1H), 7.84 (d, J = 8.8 Hz, 2H), 7.00 (d, J = 8.6 Hz, 2H), 4.06 (t, J = 6.3 Hz, 2H), 1.79-1.85 (m, 2H), 1.49-1.57 (m, 2H), 1.01 (t, J = 7.3 Hz, 3H); 13C NMR (125 MHz, CDCl3) δC (ppm): 190.7, 164.2, 131.9, 129.8, 114.7, 68.1, 31.0, 19.1, 13.7; ESI-MS: m/z 179.2 ([M+H+]);The following alkoxy benzaldehyde derivatives 4b-h were synthesizedin a similar method.P-hydroxybenzaldehyde (2.44 g, 20 mmol), potassium carbonate (4.15 g, 30 mmol) was dissolved in 50 ml DMF solution.After heating at reflux for 1 h, cool down to 35°C.Was slowly added n-bromobutane (20mmol, 2.72g), after stirring for 10min, heated under reflux for 12h.After cooling to room temperature, the solvent was removed by rotary evaporation, extracted with dichloromethane and water, and dried over anhydrous sodium sulfate.The solvent was removed by rotary evaporation, and 3.04 g of a yellow oily liquid was purified using petroleum ether and ethyl acetate (1:1 by volume).That is, a compound having a structure represented by formula (II). Its yield was determined to be 85.4percent.General procedure: These compounds were prepared according to the Williamson synthesis of ethers by a known method [22-24]. 4-hydroxybenzaldehyde (8.72 g, 71.5 mmol) was added to a solution of potassium hydroxide (4 g) in ethanol (60 mL). The mixture was treated with n-alkyl halide(71.5 mmol) (methyl iodide was used in the preparation of AGeneral procedure: 4-Hydroxybenzaldehyde (244 mg, 2 mmol) was added to a solution of 46 mg (2 mmol) of sodium ethoxide in 12 mL of ethanol and stirred until completely consumed. Solution was kept under reflux (70 °C) with magnetic stirring for 20 min. The corresponding alkylation agent (n-alkyl bromide, 2 mmol) was added to the system and the temperature was maintained at 70 °C with stirring for 48 h. Compounds 2a-d were isolated by solvent extraction (ethyl acetate/water, 3:1) and then purified by distillation. Compound 2e was fussily purified by flash chromatography in silica gel (hexane/ethyl acetate; 95:05, RGeneral procedure: In a 50 ml two-necked round-bottomed flask provided with a magnetic stirrer and condenser, a mixture of 4-hydroxybenzaldehyde 3b (3 g, 24.6 mmol) and potassium carbonate (1.57 g, 15.9 mmol, 1.5 equiv) in dry acetonitrile (20 ml) was stirred at room temperature for 30 min. To this suspension, a solution of benzylbromide (3.08 ml, 25.83 mmol, 1.05 equiv) in 10 ml of acetonirile was added dropwise during 30 min. The resulting mixture was heated at 81 °C over a period of 96 h under vigorous magnetic stirring. Then, the reaction was allowed to cool down to room temperature and the insoluble salt (KBr) was filtered off and the filtrate was concentrated in a rotary evaporator under reduced pressure. The crude residue was dried under vacuum (10

Molecular Weight:178.23
XLogP3:2.7
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:5
Exact Mass:178.099379685
Monoisotopic Mass:178.099379685
Topological Polar Surface Area:26.3
Heavy Atom Count:13
Complexity:137
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes