2,6-Lutidine Property

Melting point:

-6 °C (lit.)

Boiling point:

143-145 °C (lit.)

Density 

0.92 g/mL at 25 °C (lit.)

vapor pressure 

5.5 hPa (20 °C)

FEMA 

3540 | 2,6-DIMETHYLPYRIDINE

refractive index 

n20/D 1.497(lit.)

Flash point:

92 °F

storage temp. 

−20°C

solubility 

Chloroform (Soluble), Methanol (Slightly)

pka

6.65(at 25℃)

form 

Liquid

color 

Clear

Odor

at 1.00 % in dipropylene glycol. nutty amine woody bready cocoa oily

Odor Type

nutty

Water Solubility 

40 g/100 mL (20 ºC)

Sensitive 

Hygroscopic

JECFA Number

1317

Merck 

14,5616

BRN 

105690

Dielectric constant

7.3300000000000001

Stability:

Stable. Flammable. Incompatible with strong oxidizing agents, acid chlorides, acids, chloroformates. Protect from moisture.

LogP

0.12 at 25℃

CAS DataBase Reference

108-48-5(CAS DataBase Reference)

NIST Chemistry Reference

Pyridine, 2,6-dimethyl-(108-48-5)

EPA Substance Registry System

2,6-Dimethylpyridine (108-48-5)

Safety

Hazard Codes 

Xn,F,Xi

Risk Statements 

10-22-36/37/38-20/21/22

Safety Statements 

26-36/37-16-36-36/37/39

RIDADR 

UN 1993 3/PG 3

WGK Germany 

3

RTECS 

OK9700000

F 

8

Hazard Note 

Irritant/Flammable

TSCA 

Yes

HazardClass 

3

PackingGroup 

III

HS Code 

29333999

Hazardous Substances Data

108-48-5(Hazardous Substances Data)

Toxicity

LD50 orally in Rabbit: 400 mg/kg LD50 dermal Rabbit > 1000 mg/kg

Hazard and Precautionary Statements (GHS)

Symbol(GHS)

Signal word

Warning

Hazard statements

H226Flammable liquid and vapour

H302Harmful if swallowed

H315Causes skin irritation

H319Causes serious eye irritation

Precautionary statements

P210Keep away from heat/sparks/open flames/hot surfaces. — No smoking.

P302+P352IF ON SKIN: wash with plenty of soap and water.

P305+P351+P338IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continuerinsing.

2,6-Lutidine Chemical Properties,Usage,Production

Chemical Properties

Colorless oily liquid, melting point-5.8℃, boiling point 144℃（139-141℃，145.6-145.8℃）, density 0.9252（20/4℃）, refractive index 1.4977, flash point 33℃, soluble in dimethyl formamide, tetrahydrofuran, cold water, hot water, ethanol and ether, with mixed odor of Pyridine and mint.

Usage

2,6-Lutidine is widely used in organic synthesis as a raw material and solvent. In Pharmaceutical industry, it can be used for the production of antiatherosclerotic pyridinolcarbamate. It can also be used for the production of Cortisone acetate, hydrocortisone, niacin, lobeline and stilbazium iodide which is an anthelmintic and effective for the worm, fasciolopsis buski, whipworm, pinworm and so on. In addition, 2,6-Lutidine can be used as an auxiliaries for Pesticides, dyes, dyeing and printing and used as resin and rubber accelerator,  intermediate of hot oil stabilizer.  It  can be oxidized to produce Dimethyl pyridine acid, which can be used as the stabilizer for hydrogen peroxide and acetic acid and used to synthesize lobelidine. 2,6-Lutidine is used as various kinds of nutty essence and cocoa, coffee, meat, bread and vegetable typed essence. It is also used to synthesize drugs for the treatment and first-aid of hypertension.

Preparation

2,6-Lutidine is obtained through the separation of β-methylpyridine which is a recycled product of coal coking byproduct.

Category

flammable liquid

Toxicity grade

high toxic

Acute toxicity

oral – rat LD50: 400mg/kg

Flammability hazard characteristics

flammable in case of fire, high temperature and oxidant, releasing toxic nitrogen oxides in case of heat.

Storage

Ventilated and dry warehouse with low temperature, separated from acids.

Fire extinguishing agents

Dry powder, dry sand, carbon dioxide, foam.

Chemical Properties

Colorless to yellow liquid

Chemical Properties

2,6-Dimethylpyridine has a powerful and diffusive minty-tarry odor. It has also been described to have the odor of pyridine and peppermint

Occurrence

Reported found in bread, tea, peppermint oil, cheeses, chicken, beef, pork, beer, sherry, whiskies, cocoa, coffee, tea, oatmeal, rice bran, buckwheat and malt.

Uses

2,6-Lutidine is used as a solvent in organic synthesis and as a sterically hindered mild base. It is also used as a vulcanization accelerator for dyes, resins and rubber. It also acts as a food additive.

Uses

Isolated from the basic fraction of coal tar. A semi-volatile compound in tobacco.

Definition

ChEBI: A member of the class of methylpyridines that is pyridine carrying methyl substituents at positions 2 and 6.

Taste threshold values

Taste characteristics at 20 ppm: nutty, coffee, cocoa, musty, bready and meaty

Synthesis Reference(s)

Organic Syntheses, Coll. Vol. 2, p. 214, 1943
Tetrahedron Letters, 17, p. 383, 1976 DOI: 10.1016/S0040-4039(00)93738-9

General Description

A colorless liquid with a peppermint odor. Flash point 92°F. Less dense than water. Vapors heavier than air. Produces toxic oxides of nitrogen during combustion. Used to make other chemicals.

Air & Water Reactions

Highly flammable. Soluble in water.

Reactivity Profile

2,6-Lutidine neutralizes acids in exothermic reactions to form salts plus water. May be incompatible with isocyanates, halogenated organics, peroxides, phenols (acidic), epoxides, anhydrides, and acid halides. Flammable gaseous hydrogen may be generated in combination with strong reducing agents, such as hydrides.

Health Hazard

Inhalation or contact with material may irritate or burn skin and eyes. Fire may produce irritating, corrosive and/or toxic gases. Vapors may cause dizziness or suffocation. Runoff from fire control or dilution water may cause pollution.

Flammability and Explosibility

Flammable

Synthesis

Synthesis from ethyl acetoacetate, formaldehyde and ammonia; isolated from basic fraction of coal tar

Purification Methods

Likely contaminants include 3-and 4-picoline (similar boiling points). However, they are removed by using BF3, with which they react preferentially, by adding 4mL of BF3 to 100mL of dry fractionally distilled 2,6-lutidine and redistilling. Distillation of commercial material from AlCl3 (14g per 100mL) can also be used to remove picolines (and water). Alternatively, lutidine (100mL) can be refluxed with ethyl benzenesulfonate (20g) or ethyl p-toluenesulfonate (20g) for 1hour, then the upper layer is cooled, separated and distilled. The distillate is refluxed with BaO or CaH2, then fractionally distilled through a glass helices-packed column. 2,6-Lutidine can be dried with KOH or sodium or by refluxing with (and distilling from) BaO, prior to distillation. For purification via its picrate, 2,6-lutidine, dissolved in absolute EtOH, is treated with an excess of warm ethanolic picric acid. The precipitate is filtered off, recrystallised from acetone (to give m 163-164.5o (166-167o), and partitioned between ammonia and CHCl3/diethyl ether. The organic layer, after washing with dilute aqueous KOH, is dried with Na2SO4 and fractionally distilled. [Warnhoff J Org Chem 27 4587 1962.] Alternatively, 2,6-lutidine can be purified via its urea complex, as described under 2,3-lutidine. Other purification procedures include azeotropic distillation with phenol [Coulson et al. J Appl Chem (London) 2 71 1952], fractional crystallisation by partial freezing, and vapour-phase chromatography using a 180-cm column of polyethylene glycol-400 (Shell, 5%) on Embacel (May and Baker) at 100o, with argon as carrier gas [Bamford & Block J Chem Soc 4989 1961]. The hydrochloride has m 235-237o, 239o (from EtOH). [Beilstein 20 II 160, 20 III/IV 2776, 20/6 V 32.]