5-Ethyl-2-methylpyridine is an
organic compound
In chemistry, organic compounds are generally any chemical compounds that contain carbon-hydrogen or carbon-carbon bonds. Due to carbon's ability to catenate (form chains with other carbon atoms), millions of organic compounds are known. The ...
with the formula (C
2H
5)(CH
3)C
5H
3N. One of several isomeric
pyridine
Pyridine is a basic heterocyclic organic compound with the chemical formula . It is structurally related to benzene, with one methine group replaced by a nitrogen atom. It is a highly flammable, weakly alkaline, water-miscible liquid with a d ...
s with this formula, this derivative is of interest because it is efficiently prepared from simple reagents and it is a convenient precursor to
nicotinic acid
Niacin, also known as nicotinic acid, is an organic compound and a form of vitamin B3, an essential human nutrient. It can be manufactured by plants and animals from the amino acid tryptophan. Niacin is obtained in the diet from a variet ...
, a form of
vitamin B3. 5-Ethyl-2-methylpyridine is a colorless liquid.
Synthesis and reactions
5-Ethyl-2-methylpyridine is produced by condensation of
paraldehyde
Paraldehyde is the cyclic trimer of acetaldehyde molecules. Formally, it is a derivative of 1,3,5-trioxane, with a methyl group substituted for a hydrogen atom at each carbon. The corresponding tetramer is metaldehyde. A colourless liquid, it ...
(a derivative of
acetaldehyde
Acetaldehyde (IUPAC systematic name ethanal) is an organic chemical compound with the formula CH3 CHO, sometimes abbreviated by chemists as MeCHO (Me = methyl). It is a colorless liquid or gas, boiling near room temperature. It is one of the mos ...
) and
ammonia
Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous was ...
:
:4CH
3CHO + NH
3 → (C
2H
5)(CH
3)C
5H
3N + 4H
2O
The conversion is an example of a structurally complex compound efficiently made from simple precursors. Under related conditions, the condensation of acetaldehyde and ammonia delivers
2-picoline.
Oxidation of 5-ethyl-2-methylpyridine with nitric acid gives
nicotinic acid
Niacin, also known as nicotinic acid, is an organic compound and a form of vitamin B3, an essential human nutrient. It can be manufactured by plants and animals from the amino acid tryptophan. Niacin is obtained in the diet from a variet ...
via the decarboxylation of
2,5-pyridinedicarboxylic acid.
[
]
Toxicity
Like most alkylpyridines, the of 5-ethyl-2-methylpyridine is modest, being 368 mg/kg (oral, rat).[
]
References
{{DEFAULTSORT:Ethyl-2-methylpyridine, 5-
Pyridines
Foul-smelling chemicals