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Benzoin

Benzoin structure

CAS No:
579-44-2
Formula:
C14H12O2
Chemical Name:
Benzoin
Synonyms:
(R,S)-Benzoin;rac-(R*)-1,2-Diphenyl-2-hydroxyethanone;rac-(R*)-α-Benzoylbenzenemethanol;rac-(R*)-α-Hydroxy-α-phenylacetophenone;rac-(αR*)-α-Phenyl-α-hydroxyacetophenone;ALPHA-HYDROXY-ALPHA-PHENYLACETOPHENONE;ALPHA-HYDROXY-PHENYLACETOPHENONE;ALPHA-HYDROXYBENZYL PHENYL KETONE
Categories:
Pharmaceutical Intermediates > Bulk Drug Intermediates

Description

WHITE-TO-YELLOW CRYSTALS.

Benzoin（known as benzoin gum and benzoin resin），is a spice made from the resin obtained from wounding the trunk of several benzoin trees. The benzoin tree is distributed in Sumatra, Java and the Malay Peninsula in Indonesia, and the trade name is Sumatra benzoin; the Siamese benzoin tree is distributed in Thailand, Vietnam, Cambodia, China's Yunnan and Guangxi, and the trade name is Siam (Thailand) benzoin.

White or light yellow prismatic crystal, insoluble in cold water, slightly soluble in hot water and ether, soluble in ethanol. It can reduce Fehling's solution and react with concentrated sulfuric acid to generate bibenzoyl.

ChEBI: Benzoin is a ketone that consists of acetophenone bearing hydroxy and phenyl substituents at the alpha-position. The parent of the class of benzoins. It has a role as an EC 3.1.1.1 (carboxylesterase) inhibitor. It is a member of benzoins and a secondary alpha-hydroxy ketone.

Benzoin Basic Attributes

Molecular Weight：

212.24

Exact Mass：

212.24

EC Number：

209-441-5

HScode：

2914399090

Characteristics

PSA：

37.30000

XLogP3：

2.60290

Appearance：

Benzoin is an off-white to yellow-white crystalline solid with an odor of camphor. Slightly acrid taste. When broken the fresh surfaces have a milky-white color. (NTP, 1992)

Density：

1,31 g/cm3

Melting Point：

134-138 °C(lit.)

Boiling Point：

194 °C12 mm Hg(lit.)

Flash Point：

181°C

Refractive Index：

1.6000 (estimate)

Water Solubility：

0.3g/L(25 ºC)

Storage Conditions：

Keep container closed when not in use. Store in a cool, dry, well-ventilated area away from incompatible substances.

Vapor Pressure：

1 MM HG @ 135.6 DEG C

Odor：

SWEET NON-DESCRIPT ODOR

Taste：

SWEET NON-DESCRIPT TASTE

PH：

ALC SOLN IS ACID TO LITMUS PAPER & BECOMES MILKY UPON ADDITION OF WATER

Safety Information

Hazard category：

6.1

wgk germany：

safety instructions：

24/25

RTECS Number：

DI1590000

Stability/Shelf Life：

Stable under normal temperatures and pressures.

Precautionary statement(s)：

P273, P501

Hazard Statements：

H412

Benzoin Use and Manufacturing

Methods of Manufacturing

Benzaldehyde reacts in hot ethanol solution of potassium cyanide or sodium cyanide to produce benzoin. Cyanide ion is a special catalyst in the reaction, and most aromatic aldehydes can carry out this reaction. Because it is equivalent to the condensation of two molecules of aldehyde, this reaction is called benzoin condensation. Mix two different aldehydes together for benzoin condensation to obtain mixed benzoin. Mix benzaldehyde and ethanol, adjust the pH to 7-8 with sodium hydroxide solution, add 3% sodium cyanide solution, reflux at 75-80℃ for 0.5h, cool to below 10℃, filter, and wash the filter cake until nothing Benzoin is obtained from cyanide, and the yield is over 90%.

Uses

Used as pharmaceutical intermediates, also used in the production of dyes and light sensitizers for photosensitive resins, gravure inks, photocurable coatings

DL-Benzoin has anti-oxidant and anti-aging properties in medicine, and has a diuretic effect when taken orally. It can also be used as an expectorant for chronic bronchitis. It is widely used as an additive in cosmetics such as perfume, soap, detergent, vanishing cream, etc.