1-Propanol

Propan-1-ol is a primary alcohol with the formula CH₃CH₂CH₂OH. It is also known as 1-propanol, 1-propyl alcohol, n-propyl alcohol, or simply propanol. It is an isomer of propan-2-ol. It is used as a solvent in the pharmaceutical industry, and for resins and cellulose esters. It is formed naturally in small amounts during many fermentation processes.

Chemical properties

1-Propanol shows the normal reactions of a primary alcohol. Thus it can be converted to alkyl halides; for example red phosphorus and iodine produce n-propyl iodide in 90% yield, while PCl₃ with catalytic ZnCl₂ gives 1-chloropropane. Reaction with acetic acid in the presence of an H₂SO₄ catalyst under Fischer esterification conditions gives propyl acetate, while refluxing propanol overnight with formic acid alone can produce propyl formate in 65% yield. Oxidation of 1-propanol with Na₂Cr₂O₇ and H₂SO₄ gives only a 36% yield of propionaldehyde, and therefore for this type of reaction higher yielding methods using PCC or the Swern oxidation are recommended. Oxidation with chromic acid yields propionic acid

Some example reactions of 1-propanol

Preparation

1-Propanol is a major constituent of fusel oil, a by-product formed from certain amino acids when potatoes or grains are fermented to produce ethanol. This is no longer a significant source of propanol.

1-Propanol is manufactured by catalytic hydrogenation of propionaldehyde. The propionaldehyde is itself produced via the oxo process, by hydroformylation of ethylene using carbon monoxide and hydrogen in the presence of a catalyst such as cobalt octacarbonyl or a rhodium complex.

(1) H₂C=CH₂ + CO + H₂ → CH₃CH₂CH=O

(2) CH₃CH₂CH=O + H₂ → CH₃CH₂CH₂OH

A traditional laboratory preparation of 1-propanol involves treating n-propyl iodide with moist Ag₂O.

History

1-Propanol was discovered in 1853 by Chancel, who obtained it by fractional distillation of fusel oil.

References

1. Furniss, B. S.; Hannaford, A. J.; Smith, P. W. G.; Tatchell, A. R. (1989), Vogel's Textbook of Practical Organic Chemistry (5th ed.), Harlow: Longman, ISBN 0-582-46236-3
2. Handbook of Chemistry and Physics, 71st edition, CRC Press, Ann Arbor, Michigan, 1990.
3. The Merck Index, 7th edition, Merck & Co, Rahway, New Jersey, USA, 1960.
4. Perkin, W. H.; Kipping, F. S. (1922). Organic Chemistry, London: W. & R. Chambers.

External links

• International Chemical Safety Card 0553
• NIOSH Pocket Guide to Chemical Hazards