Background and overview[1][2]
Benzyl butyrate is also called benzyl butyrate. It appears as a colorless liquid with a sweet, fruity, vanilla, apple, pineapple, tropical fruit aroma and a sweet, apricot, pear, fruity, vanilla flavor. The molecular formula is CHO, the molecular weight is 178.23, and the boiling point is 240°C. It is insoluble in water and soluble in organic solvents such as alcohol and ether. It is mainly used in edible flavors such as apricots, coconuts, plums, peaches, pineapples, strawberries, cheese, cream, and rose wine. A small amount is used in daily flavors such as jasmine, hyacinth, succulent, lily of the valley, and roses.
Preparation[1-2]
Method 1,
Put 110g (1mol) of sodium butyrate, 151.8g (1.2mol) of benzyl chloride, 550g of toluene, and 4.4g of triethylamine into the flask, start stirring, raise the temperature and reflux for 4-8 hours, until the chlorination is analyzed by GC End the reaction when the benzyl content no longer changes, cool down, and filter out the sodium chloride produced by the reaction to obtain a crude product containing benzyl chloride, phase transfer catalyst and toluene solvent.
After recovering excess benzyl chloride, phase transfer catalyst and toluene solvent from the above crude product under normal pressure, it is then rectified under reduced pressure to obtain the finished product benzyl butyrate. The effective amount of product is 170g, and the yield is 95.5%.
Method 2,
Add n-butyraldehyde (0.5mmol, 36mg), benzyl bromide (1mmol, 171mg), water (2mL), tert-butyl hydroperoxide (1mmol, 138μL, 70wt% aqueous solution) and tetracycline into a 25mL pressure tube. Butylammonium iodide (0.5mmol, 185mg), then seal the pressure-resistant tube and place it in an oil bath, stir and react at 80°C for 2 hours. After the reaction, 10 mL of water was added, extracted with ethyl acetate (10 mL × 3), the organic phases were combined, washed with Na2S2O3 aqueous solution, and then dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure and then separated through a silica gel column (petroleum ether/ethyl acetate = 60/1) to obtain benzyl butyrate (46 mg, 52%). The characterization data of this compound are as follows: 1HNMR (MHz, CDCl3)δ: 0.95 (t, J = 7.2Hz, 3H), 1.63-1.73 (m, 2H ),2.34(t,J＝7.2Hz, 2H),5.12(s,2H),7.32-7.37(m,5H).13CNMR(100MHz, CDCl3)δ:13.7,18.5,36.2,66.1, 128.2,128.6,136.1,173.8.MS:m/z201[MNa]+.
Main reference materials
[1]CN201811268806.3 Preparation method of benzyl butyrate
[2][China invention, China invention authorization] CN201610586515.3 A synthesis method of ester compounds
