Synthesis of Isopentyl Acetate

Overview

Isopentyl acetate is a small, naturally occurring ester that possesses a strong banana-like odor. Isopentyl acetate is actually found in bananas and is frequently referred to as “banana oil,” but it is found in many other organisms as well. The wide distribution of isopentyl acetate throughout nature stems, no doubt, from its close structural similarity to isopentyl pyrophosphate, another naturally occurring compound that is used by virtually every organism on the planet as a starting point for the synthesis of more complicated structures essential to cell function.

The demonstration that organic compounds can be prepared in the laboratory from other compounds, i.e., outside of a living organism, transformed the scientific world in the 19th century. Prior to this discovery scientists had subscribed to the theory of vitalism, a theory that held that organic compounds were embued with a special vital force and could only form in living organisms.

Although many naturally occurring organic compounds have been prepared in the laboratory, vitalist beliefs linger on. For example, advocates for ‘natural’ vitamins (vitamins extracted from biological organisms) claim that these compounds provide extra health benefits that cannot be obtained from ‘synthetic’ vitamins (the same compounds prepared in a laboratory). Likewise, advocates for ‘natural’ flavorings and scents have argued that these compounds are safer than their synthetic versions.

This experiment provides an opportunity to attempt the synthesis of a naturally occurring compound. It also illustrates some of the ways that a compound, natural or synthetic, can be characterized and allows you to decide how ‘natural’ and ‘synthetic’ versions of the same compound might be distinguished.