Dilleniales is an Order closely related to Caryophyllales in the Apg3 classification. They have many similarities with Magnoliidae. Dilleniales has one Family, Dilleniaceae.
The placement of Dilleniaceae has been quite problematic. In the Dahlgren system they gave the name to the Dilleniadeae, a clade that was polyphyletic and does not exist anymore in the Apg classification. In the Apg classification the position of the Dilleniaceae has been wandering, from being near the Rosidae to being near the Caryophyllales or completely unclear. They are on one hand quite developed but on the other hand look very much like Magnoliidae. This combination supports the hypothesis that the Dilleniales are the second clade of the Asteranae Class. It leads to the combination of just Carbon series and Lanthanides.