1-Propanol


1-Propanol is a primary alcohol with the formula . This colorless liquid is also known as propan-1-ol, 1-propyl alcohol, n-propyl alcohol, and n-propanol. It is an isomer of 2-propanol. It is formed naturally in small amounts during many fermentation processes and used as a solvent in the pharmaceutical industry, mainly for resins and cellulose esters, and, sometimes, as a disinfecting agent.

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 80% yield, while phosphorus trichloride| with catalytic Zinc chloride| gives n-propyl chloride. Reaction with acetic acid in the presence of an sulfuric acid| 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 Sodium dichromate| and 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.

Preparation

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.
A traditional laboratory preparation of 1-propanol involves treating n-propyl iodide with moist silver oxide|.
1-Propanol was discovered in 1853 by Gustave C. B. Chancel, who obtained it by fractional distillation of fusel oil. Indeed, 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 process is no longer a significant source of 1-propanol.

Safety

1-Propanol is thought to be similar to ethanol in its effects on the human body, but 2–4 times more potent. Oral LD50 in rats is 1870 mg/kg. It is metabolized into propionic acid. Effects include alcoholic intoxication and high anion gap metabolic acidosis. As of 2011, only one case of lethal 1-propanol poisoning was reported.

Propanol as fuel

1-propanol has high octane numbers and it is suitable for engine fuel usage. However, the production of propanol has been too expensive to make it a common fuel. The research octane number of propanol is 118 and anti-knock index is 108.