Amyl: A Misunderstood Word

There is much confusion associated with the word amyl. For example, many textbooks draw a structural formula of n-pentyl acetate rather than isopentyl acetate when referring to the chief component of banana oil (amyl acetate). When younger chemists are taught to use the words propyl, butyl, and pentyl in place of n-propyl, n-butyl, and n-pentyl, they then incorrectly assume that this practice also applies to the word amyl. As is the case with banana oil, if the word amyl is going to be used to refer to just one of the isomeric pentyl groups, it should rightfully be isopentyl. The reason for this dates back to an abundant and important article of commerce called amylic alcohol (also called potato oil) which consisted chiefly of isopentyl alcohol. In fact, one can look in various chemical catalogs and handbooks of today and see such names as amyl benzoate and amyl nitrite used in place of isopentyl benzoate and isopentyl nitrite. Adding to all the confusion is the common practice of using the word amyl along with the singular form of another word when referring to an isomeric mixture; i.e. using amyl acetate rather than amyl acetates when referring to a mixture of pentyl acetates.