2,6-Lutidine
Encyclopedia
2,6-Lutidine is a natural heterocyclic
aromatic
organic compound
. It has been isolated from the basic
fraction of coal tar
and from bone oil
. It is a dimethyl
substituted derivative of pyridine
. It has been detected in waste water from oil shale processing sites and former creosoting facilities. 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, however the neat solvent has a pungent, noxious odor.
2,6-Lutidine is weakly nucleophilic, due to the steric effects of the two methyl groups on the ring nitrogen. It is moderately basic, with a pKa of 6.60. In organic synthesis
, 2,6-lutidine is thus widely used as a sterically hindered
mild base.
is an excellent source of carbon, nitrogen, and energy for certain microorganisms, methylation significantly retards degradation of the pyridine ring. 2,6-Lutidine was found to be significantly more resistant to microbiological degradation than any of the picoline
isomers or 2,4-lutidine in soil. Significant volatilization loss was observed in liquid media. Estimated time for complete degradation was > 30 days.
Heterocyclic compound
A heterocyclic compound is a cyclic compound which has atoms of at least two different elements as members of its ring. The counterparts of heterocyclic compounds are homocyclic compounds, the rings of which are made of a single element....
aromatic
Aromaticity
In organic chemistry, Aromaticity is a chemical property in which a conjugated ring of unsaturated bonds, lone pairs, or empty orbitals exhibit a stabilization stronger than would be expected by the stabilization of conjugation alone. The earliest use of the term was in an article by August...
organic compound
Organic compound
An organic compound is any member of a large class of gaseous, liquid, or solid chemical compounds whose molecules contain carbon. For historical reasons discussed below, a few types of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon, and cyanides, as well as the...
. It has been isolated from the basic
Base (chemistry)
For the term in genetics, see base A base in chemistry is a substance that can accept hydrogen ions or more generally, donate electron pairs. A soluble base is referred to as an alkali if it contains and releases hydroxide ions quantitatively...
fraction of coal tar
Coal tar
Coal tar is a brown or black liquid of extremely high viscosity, which smells of naphthalene and aromatic hydrocarbons. Coal tar is among the by-products when coal iscarbonized to make coke or gasified to make coal gas...
and from bone oil
Dippel's oil
Dippel's Oil is a nitrogenous by-product of the destructive distillation manufacture of bone char . This liquid is dark colored and highly viscous with an unpleasant smell. The oil contains the organic base pyrrole. It is named after its inventor, Johann Conrad Dippel,Dippel's oil had a number...
. It is a dimethyl
Methyl group
Methyl group is a functional group derived from methane, containing one carbon atom bonded to three hydrogen atoms —CH3. The group is often abbreviated Me. Such hydrocarbon groups occur in many organic compounds. The methyl group can be found in three forms: anion, cation and radical. The anion...
substituted derivative of pyridine
Pyridine
Pyridine is a basic heterocyclic organic compound with the chemical formula C5H5N. It is structurally related to benzene, with one C-H group replaced by a nitrogen atom...
. It has been detected in waste water from oil shale processing sites and former creosoting facilities. 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, however the neat solvent has a pungent, noxious odor.
2,6-Lutidine is weakly nucleophilic, due to the steric effects of the two methyl groups on the ring nitrogen. It is moderately basic, with a pKa of 6.60. In organic synthesis
Organic synthesis
Organic synthesis is a special branch of chemical synthesis and is concerned with the construction of organic compounds via organic reactions. Organic molecules can often contain a higher level of complexity compared to purely inorganic compounds, so the synthesis of organic compounds has...
, 2,6-lutidine is thus widely used as a sterically hindered
Steric effects
Steric effects arise from the fact that each atom within a molecule occupies a certain amount of space. If atoms are brought too close together, there is an associated cost in energy due to overlapping electron clouds , and this may affect the molecule's preferred shape and reactivity.-Steric...
mild base.
Environmental Properties
Though pyridinePyridine
Pyridine is a basic heterocyclic organic compound with the chemical formula C5H5N. It is structurally related to benzene, with one C-H group replaced by a nitrogen atom...
is an excellent source of carbon, nitrogen, and energy for certain microorganisms, methylation significantly retards degradation of the pyridine ring. 2,6-Lutidine was found to be significantly more resistant to microbiological degradation than any of the picoline
Picoline
Picoline refers to three different methylpyridine isomers, all with the chemical formula C6H7N and a molar mass of 93.13 g mol−1. All three are colourless liquids at room temperature and pressure and are miscible with water and most organic solvents...
isomers or 2,4-lutidine in soil. Significant volatilization loss was observed in liquid media. Estimated time for complete degradation was > 30 days.