Niacin

Niacin

Names
IUPAC name Pyridine-3-carboxylic acid
Other names Bionic Nicotinic acid Vitamin B3
Identifiers
Jmol-3D images	Image
SMILES c1cc(cnc1)C(=O)O
Properties
Chemical formula	C6H5NO2
Molar mass	123.1094 g/mol
Appearance	White solid
Odor	Odorless
Density	1.473 g/cm3
Melting point	237 °C (459 °F; 510 K)
Boiling point	Sublimes
Solubility in water	1.8 g/100 ml (20 °C)
Solubility	Soluble in DMSO Slightly soluble in diethyl ether, ethanol Insoluble in lipids
Vapor pressure	5.7·10-6 mmHg °C
Acidity (pKa)	4.75
Thermochemistry
Std enthalpy of formation (ΔfHo298)	−344.9 kJ/mol
Hazards
Safety data sheet	Sigma-Aldrich
Flash point	193 °C
Related compounds
Related compounds	Dipicolinic acid Pyridine
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references

Niacin, also known as nicotinic acid or vitamin B3, is an organic compound with the formula C₆H₅NO₂. It is an important essential human nutrient.

Properties

Chemical

Decarboxylation of niacin gives pyridine

C₆H₅NO₂ → C₅H₅N + CO₂

Copper chromite is used as a catalyst.

Physical

Niacin is a white solid, slightly soluble in water, but more so in organic solvents.

Availability

Niacin can be easily found in various Vitamin B3 supplements. To extract it, simply crush the niacin in a mortar or better in a coffee grinder. Add sodium hydroxide to convert it into the more soluble sodium nicotinate, and vacuum filter the solution. Convert it back to nicotinic acid by carefully adding hydrochloric acid. Since niacin is poorly soluble in water, it will precipitate out of the solution. The resulting precipitate is filtered, however, this is difficult to do, as niacin water suspensions are non-Newtonian fluids, similar to starch and water mixtures. The resulting precipitate should be air-dried, as vacuum drying doesn't work very well. The yield from this method is about 50-70%. Using an organic solvent will improve the yield.

Niacin however is best purchased in bulk, rather than extracted from pills. It can be purchased online relatively cheap.

Preparation

Niacin is best purchased than prepared.

It can be isolated from the oxidation of nicotine. Nitric acid is commonly used.

Projects

• Make pyridine
• Make arecoline

Handling

Safety

Niacin is edible, but avoid consuming lab-grade nicotinic acid.

Storage

Niacin should be stored in closed bottles.

Disposal

No special disposal is required. Discard it as you wish.

References

Relevant Sciencemadness threads

• Niacin from nicotine?
• Niacin Chlorochromate (NCC??) for oxidation of alcohols