| 31/00 | Reduction in general |
| 33/00 | Oxidation in general |
| 35/00 | Reactions without formation or introduction of functional groups containing hetero atoms, involving a change in the type of bonding between two carbon atoms already directly linked |
| 35/02 | Reactions without formation or introduction of functional groups containing hetero atoms, involving a change in the type of bonding between two carbon atoms already directly linked Reduction |
| 35/04 | Reactions without formation or introduction of functional groups containing hetero atoms, involving a change in the type of bonding between two carbon atoms already directly linked Dehydrogenation |
| 35/06 | Reactions without formation or introduction of functional groups containing hetero atoms, involving a change in the type of bonding between two carbon atoms already directly linked Decomposition, e.g. elimination of halogens, water or hydrogen halides |
| 35/08 | Reactions without formation or introduction of functional groups containing hetero atoms, involving a change in the type of bonding between two carbon atoms already directly linked Isomerisation |
| 37/00 | Reactions without formation or introduction of functional groups containing hetero atoms, involving either the formation of a carbon-to-carbon bond between two carbon atoms not directly linked already or the disconnection of two directly linked carbon atoms |
| 37/02 | Reactions without formation or introduction of functional groups containing hetero atoms, involving either the formation of a carbon-to-carbon bond between two carbon atoms not directly linked already or the disconnection of two directly linked carbon atoms Addition |
| 37/04 | Reactions without formation or introduction of functional groups containing hetero atoms, involving either the formation of a carbon-to-carbon bond between two carbon atoms not directly linked already or the disconnection of two directly linked carbon atoms Substitution |
| 37/06 | Reactions without formation or introduction of functional groups containing hetero atoms, involving either the formation of a carbon-to-carbon bond between two carbon atoms not directly linked already or the disconnection of two directly linked carbon atoms Decomposition, e.g. elimination of carbon dioxide |
| 37/08 | Reactions without formation or introduction of functional groups containing hetero atoms, involving either the formation of a carbon-to-carbon bond between two carbon atoms not directly linked already or the disconnection of two directly linked carbon atoms Isomerisation |
| 37/10 | Reactions without formation or introduction of functional groups containing hetero atoms, involving either the formation of a carbon-to-carbon bond between two carbon atoms not directly linked already or the disconnection of two directly linked carbon atoms Cyclisation |
| 37/12 | Reactions without formation or introduction of functional groups containing hetero atoms, involving either the formation of a carbon-to-carbon bond between two carbon atoms not directly linked already or the disconnection of two directly linked carbon atoms Cyclisation Diels-Alder reactions |
| 39/00 | Halogenation |
| 41/00 | Formation or introduction of functional groups containing oxygen |
| 41/02 | Formation or introduction of functional groups containing oxygen of hydroxy or O-metal groups |
| 41/04 | Formation or introduction of functional groups containing oxygen of ether, acetal or ketal groups |
| 41/06 | Formation or introduction of functional groups containing oxygen of carbonyl groups |
| 41/08 | Formation or introduction of functional groups containing oxygen of carboxyl groups or salts, halides or anhydrides thereof |