Have you ever read a detergent label and got confused? Or had trouble understanding a medication recall? Certain chemical names seem like a bizarre language that's randomly composed with numbers and letters, as well as lengthy words with countless syllables. Welcome to the nomenclature of organic chemistry.
Do the names 2-acetoxybenzoic acid, (4Z,7Z,10Z,13Z,16Z,19Z)-docosa-4,7,10,13,16,19-hexaenoic acid, or (2R,3S,4R,5R)-2,3,4,5,6-pentahydroxyhexanal ring a bell? Your life may not be able to go without these compounds. They are aspirin, DHA (an omega-3 fatty acid that's often found in sea fish), and glucose.
Their official chemical names are generated by a set of naming rules, created and developed by the International Union of Pure and Applied Chemistry (IUPAC). Its systematic approach ensures a global standard that everyone can follow. If someone discovers or synthesizes a new compound, and gives it an IUPAC name, others can easily redraw the structure of the molecule according to its official chemical name.
Learning about such a complex system sounds daunting. Fortunately, it has the three basic pinciples that's easy to remember and apply. The first step is to identify the longest carbon chain and give it a root name. Then find the highest priority functional group and add its suffix to the root name. Lastly, identify the types of substituents and locate their positions on the main chain, and then add a numbered prefix to the root name.
Take aspirin for example, its root name "benzoic acid" is the main body of the pain reliever molecule. Its structure resembles a formic acid (HCOOH) linked to a benzene (C6H6) ring. The "acetyl" (CH3COO-) moiety is its only functional group, which contains a methyl group single-bonded to a carbonyl. The "2-" is the number prefix that described where the actyl group is on the main chain, which is the second position on the benzene ring.
Try applying the three principles next time you see a chemical name, you may be able to pick apart different groups of the molecule, and perhaps figure out what it's made of.
Source: CrashCourse via Youtube
