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How to convert an IUPAC name to a structure, and a structure to a name

Tutorial · macOS and Windows

ChemPencil names structures and draws structures from names, offline and instantly. It covers the families you meet most in teaching and everyday work: alkanes, alcohols, amines, halides, aldehydes, ketones, carboxylic acids, esters, ethers and acid chlorides, common ring systems, substituted benzenes and heterocycles, with (R)/(S) for stereocentres.

Structure from a name

  1. Choose Structure › Structure from Name….
  2. Type the name, for example 4-nitrophenol, 2-methylpropan-1-ol or (S)-2-aminopropanoic acid. Common retained names such as benzoic acid, phenol, aniline, pyridine and furan work too.
  3. Click OK. The structure is drawn, with a wedge for any (R)/(S) centre.
The Structure from Name dialog with 4-nitrophenol typed in
Structure from Name.

Name a structure

  1. Draw the structure.
  2. Choose Structure › Generate Name. The IUPAC name is added as a text label under the first molecule.
  3. To name just part of a drawing, or one molecule among several, select it, right-click it and choose Generate Name for Selection.
(R)-butan-2-ol with its generated name under it
A generated name, with its stereodescriptor.

Some examples of what you get:

CC(C)CO 2-methylpropan-1-ol CC(=O)OCC ethyl ethanoate CC(=O)Cl ethanoyl chloride CCOCC 1-ethoxyethane OC(=O)c1ccccc1O 2-hydroxybenzoic acid CC[C@@H](C)O (R)-butan-2-ol
On Windows, View › IUPAC Name shows the name of the first molecule as you draw, with a Copy button. When no name can be generated (for example for complex fused polycycles) the computer beeps; use the InChIKey to look the compound up instead.

Try it yourself. ChemPencil runs on macOS 12 and later and on Windows 10 and 11.

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