(R)-(-)-1,2-Propanediol Property

Melting point:

-57C

Boiling point:

186-188 °C765 mm Hg(lit.)

alpha 

-17 º (c=neat)

Density 

1.04 g/mL at 25 °C(lit.)

refractive index 

n20/D 1.434(lit.)

Flash point:

225 °F

storage temp. 

Inert atmosphere,Room Temperature

solubility 

Miscible with acetone, chloroform, ethanol (95%), glycerin, and water; soluble at 1 in 6 parts of ether; not miscible with light mineral oil or fixed oils, but will dissolve some essential oils.

pka

14.49±0.20(Predicted)

form 

clear liquid

color 

Colorless to Light orange to Yellow

Specific Gravity

1.036

optical activity

[α]20/D 16.5°, neat

Sensitive 

Hygroscopic

Merck 

14,7855

BRN 

1718872

CAS DataBase Reference

4254-14-2(CAS DataBase Reference)

NIST Chemistry Reference

R-(-)-1,2-propanediol(4254-14-2)

Safety

Hazard Codes 

F,Xn

Risk Statements 

20-65-15-10

Safety Statements 

24/25-43-7/8

WGK Germany 

1

F 

3

HS Code 

29053200

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H319Causes serious eye irritation

Precautionary statements

P264Wash hands thoroughly after handling.

P264Wash skin thouroughly after handling.

P280Wear protective gloves/protective clothing/eye protection/face protection.

(R)-(-)-1,2-Propanediol Chemical Properties,Usage,Production

Chemical Properties

Colorless to light yellow liqui

Chemical Properties

Propylene glycol is a clear, colorless, viscous, practically odorless liquid, with a sweet, slightly acrid taste resembling that of glycerin.

Uses

R-(-)-1,2-Propanediol, is a chiral building blocks that can be used for variety of chemical synthesis.

Definition

ChEBI: (R)-propane-1,2-diol is a propane-1,2-diol. It has a role as a human metabolite and an Escherichia coli metabolite. It is an enantiomer of a (S)-propane-1,2-diol.

Production Methods

Propylene is converted to chlorohydrin by chlorine water and hydrolyzed to 1,2-propylene oxide. With further hydrolysis, 1,2- propylene oxide is converted to propylene glycol.

Pharmaceutical Applications

Propylene glycol has become widely used as a solvent, extractant, and preservative in a variety of parenteral and nonparenteral pharmaceutical formulations. It is a better general solvent than glycerin and dissolves a wide variety of materials, such as corticosteroids, phenols, sulfa drugs, barbiturates, vitamins (A and D), most alkaloids, and many local anesthetics.
As an antiseptic it is similar to ethanol, and against molds it is similar to glycerin and only slightly less effective than ethanol. Propylene glycol is commonly used as a plasticizer in aqueous film-coating formulations.
Propylene glycol is also used in cosmetics and in the food industry as a carrier for emulsifiers and as a vehicle for flavors in preference to ethanol, since its lack of volatility provides a more uniform flavor.

Safety

Propylene glycol is used in a wide variety of pharmaceutical formulations and is generally regarded as a relatively nontoxic material. It is also used extensively in foods and cosmetics. Probably as a consequence of its metabolism and excretion, propylene glycol is less toxic than other glycols. Propylene glycol is rapidly absorbed from the gastrointestinal tract; there is also evidence that it is absorbed topically when applied to damaged skin. It is extensively metabolized in the liver, mainly to lactic and pyruvic acids, and is also excreted unchanged in the urine.
In topical preparations, propylene glycol is regarded as minimally irritant,although it is more irritant than glycerin. There have been some reports of contact dermatitis associated with propylene glycol.Some local irritation is produced upon application to mucous membranes or when it is used under occlusive conditions.Parenteral administration may cause pain or irritation when propylene glycol is used in high concentration. Propylene glycol is estimated to be one-third as intoxicating as ethanol, with administration of large volumes being associated with adverse effects most commonly on the central nervous system, especially in neonates and children.Other adverse reactions reported, though generally isolated, include: ototoxicity;cardiovascular effects; seizures; and hyperosmolarity and lactic acidosis, both of which occur most frequently in patients with renal impairment. Adverse effects are more likely to occur following consumption of large quantities of propylene glycol or on adminstration to neonates, children under 4 years of age, pregnant women, and patients with hepatic or renal failure. Adverse events may also occur in patients treated with disulfiram or metronidazole.
On the basis of metabolic and toxicological data, the WHO has set an acceptable daily intake of propylene glycol at up to 25 mg/kg body-weight.Formulations containing 35% propylene glycol can cause hemolysis in humans.
In animal studies, there has been no evidence that propylene glycol is teratogenic or mutagenic. Rats can tolerate a repeated oral daily dose of up to 30 mL/kg body-weight in the diet over 6 months, while the dog is unaffected by a repeated oral daily dose of 2 g/kg in the diet for 2 years.
(mouse, IP): 9.72 g/kg
(mouse, IV): 6.63 g/kg
(mouse, oral): 22.0 g/kg
(mouse, SC): 17.34 g/kg
(rat, IM): 0.01 g/kg
(rat, IP): 6.66 g/kg
(rat, IV): 6.42 g/kg
(rat, oral): 0.02 g/kg
(rat, SC): 22.5 g/kg

storage

At cool temperatures, propylene glycol is stable in a well-closed container, but at high temperatures, in the open, it tends to oxidize, giving rise to products such as propionaldehyde, lactic acid, pyruvic acid, and acetic acid. Propylene glycol is chemically stable when mixed with ethanol (95%), glycerin, or water; aqueous solutions may be sterilized by autoclaving.
Propylene glycol is hygroscopic and should be stored in a wellclosed container, protected from light, in a cool, dry place.

Incompatibilities

Propylene glycol is incompatible with oxidizing reagents such as potassium permanganate.

Regulatory Status

GRAS listed. Accepted for use as a food additive in Europe. Included in the FDA Inactive Ingredients Database (dental preparations; IM and IV injections; inhalations; ophthalmic, oral, otic, percutaneous, rectal, topical, and vaginal preparations). Included in nonparenteral and parenteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients.