1-Propanol
1-Propanol is a primary alcohol with the formula and sometimes represented as PrOH or n-PrOH. It is a colourless liquid and an isomer of 2-propanol. 1-Propanol is used as a solvent in the pharmaceutical industry, mainly for resins and cellulose esters, and, sometimes, as a disinfecting agent.
History
The compound was discovered by Gustave Chancel in 1853 by fractional distillation of fusel oil. He measured its boiling point at 96°C, correctly identified its empirical formula, studied some of its chemical properties and gave it two names: propionic alcohol and hydrate of trityl.After several unsuccessful attempts, it was synthesized independently and by two different routes by Eduard Linnemann and Carl Schorlemmer in 1868.
Occurrence
Fusel alcohols like 1-Propanol are grain fermentation byproducts, and therefore trace amounts of 1-Propanol are present in many alcoholic beverages.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 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. Propionaldehyde is 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.Other proposed industrial processes include the two-step isomerization and hydrogenation of propylene oxide.
A traditional laboratory preparation of 1-propanol involves treating n-propyl iodide with moist [silver(I) oxide|].