We are pleased to introduce version 11.7 of our ChemDoodle 2D software. This update is free for all ChemDoodle subscriptions, Lifetime and Site licenses. Licenses are as little as $15, and we have a free trial available at: https://www.chemdoodle.com/


Various ions named by ChemDoodle 2D. ChemDoodle 2D has many options for naming, some of the relevant ion options are shown.

Executive Summary

ChemDoodle 2D v11.7 is a feature update. The main new feature is expert IUPAC naming support for ions, as well as other IUPAC naming features.


  1. IUPAC naming support for ions, including radical ions. Both positive and negative, with differences in electrons or protons, as well as combinations of charge centers on a single molecule are supported. This is by traditional rules with IUPAC Red Book 2005 clarifications.
  2. Support for naming neutral and charged elements, as defined by the 2005 Red Book.
  3. Full support for ring assemblies (up to 10 units, max for traditional naming). Over 10 repeating units will be named substitutively. Previously, only 2 unit ring assemblies were supported.
  4. Revised support for hydros and H locants. Also support for oxo fused H locants.
  5. Added the following new traditional IUPAC naming options: (1) detach hydros from the front of of base names, which will instead be treated as substituents, (2) exclude H locants on predefined heterocyclic trivial and semi-trivial systems where the hydrogen is on an unabiguous pnictogen atom as defined in the '79 Blue Book, (3) whether or not to always force the radical suffix as the final suffix, (4) disable functional group mapping, (5) use explicit cation/anion naming.


  1. Reconcilled radical IUPAC naming support with the 2005 Red Book.