2,6-Lutidine
<templatestyles src="Chembox/styles.css"/>
Template:Chembox image cellTemplate:Chembox AllOtherNamesTemplate:Chembox headerbarTemplate:Chembox IndexlistTemplate:Chembox JmolTemplate:Chembox ChEMBLTemplate:Chembox ECHATemplate:Chembox E numberTemplate:Chembox IUPHAR ligandTemplate:Chembox UNIITemplate:Chembox CompToxTemplate:Chembox headerbarTemplate:Chembox SolubilityInWaterTemplate:Chembox headerbarTemplate:Chembox Datapage checkTemplate:Chembox Footer| Template:Longitem | Template:Unbulleted list |
| Template:Longitem | 105690 |
| ChEBI | Template:Unbulleted list |
| ChemSpider | Template:Unbulleted list |
| DrugBank | Template:Unbulleted list |
| EC Number | Template:Unbulleted list |
| Template:Longitem | 2863 |
| KEGG | Template:Unbulleted list |
| Template:Longitem | Template:Unbulleted list |
| RTECS number | Template:Unbulleted list |
| UN number | 2734 |
| Script error: No such module "collapsible list". | |
| Script error: No such module "collapsible list". | |
| Template:Longitem | C7H9N |
| Molar mass | 107.153 g/mol |
| Appearance | colorless oily liquid |
| Density | 0.9252 |
| Melting point | Template:Chembox CalcTemperatures |
| Boiling point | Template:Chembox CalcTemperatures |
| Acidity (pKa) | 6.72[2] |
| Template:Longitem | Script error: No such module "val". |
| NFPA 704 (fire diamond) | Template:NFPA 704 diamond |
Template:Chembox Footer/trackingScript error: No such module "TemplatePar".Template:Short description
2,6-Lutidine is a natural heterocyclic aromatic organic compound with the formula (CH3)2C5H3N. It is one of several dimethyl-substituted derivative of pyridine, all of which are referred to as lutidines. It is a colorless liquid with mildly basic properties and a pungent, noxious odor.
Occurrence and production
It was first isolated from the basic fraction of coal tar and from bone oil.[1]
A laboratory route involves condensation of ethyl acetoacetate, formaldehyde, and an ammonia source to give a bis(carboxy ester) of a 2,6-dimethyl-1,4-dihydropyridine, which, after hydrolysis, undergoes decarboxylation.[3]
It is produced industrially by the reaction of formaldehyde, acetone, and ammonia.[2]
Uses
2,6-Lutidine has been evaluated for use as a food additive owing to its nutty aroma when present in solution at very low concentrations.
Due to the steric effects of the two methyl groups, 2,6-lutidine is less nucleophilic than pyridine. Protonation of lutidine gives lutidinium, [(CH3)2C5H3NH]+, salts of which are sometimes used as a weak acid because the conjugate base (2,6-lutidine) is so weakly coordinating. In a similar implementation, 2,6-lutidine is thus sometimes used in organic synthesis as a sterically hindered mild base.[4] One of the most common uses for 2,6-lutidine is as a non-nucleophilic base in organic synthesis. It takes part in the formation of silyl ethers as shown in multiple studies.[5][6]
Oxidation of 2,6-lutidine with air gives 2,6-diformylpyridine:
- C5H3N(CH3)2 + 2 O2 → C5H3N(CHO)2 + 2 H2O
Biodegradation
The biodegradation of pyridines proceeds via multiple pathways.[7] Although pyridine is an excellent source of carbon, nitrogen, and energy for certain microorganisms, methylation significantly retards degradation of the pyridine ring. In soil, 2,6-lutidine is significantly more resistant to microbiological degradation than any of the picoline isomers or 2,4-lutidine.[8] Estimated time for complete degradation was over 30 days.[9]
See also
Toxicity
Like most alkylpyridines, the LD50 of 2,6-dimethylpyridine is modest, being 400 mg/kg (oral, rat).[2]
References
<templatestyles src="Reflist/styles.css" />
- ↑ a b Template:Merck11th
- ↑ a b c Template:Ullmann
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
Script error: No such module "Check for unknown parameters".