This is Jonathon Vandezande, the Director of Computational Chemistry here at Rowan. Today I will be providing an overview of running a bond-dissociation energy prediction with the Rowan Scientific platform.
Bond-dissociation energies are useful for predicting metabolism and degradation. The weakest bonds tend to be metabolized and degraded first, so it is useful to have a quick method to predict the bond-dissociation energy so that the molecule can be modified to reduce possible metabolism and degradation.
To run a bond-dissociation energy prediction, first log into labs.rowansci.com and select "New BDE prediction". You can upload a molecule with one of our standard molecule inputs, or you can input it from a remote database including PubChem or Materials Project. Today, we will be working with ibuprofen and uploading it from PubChem.
You can see here the ibuprofen molecule and all of the various C–H bonds, both aromatic and aliphatic. We can add individual bonds, or we can add groups of bonds including C–H and C–X bonds. For this tutorial, we will be using all C–H bonds and running it in RAPID mode. This will take a few minutes, so we will go ahead and flip over to an already completed version of this molecule.
Here we can see the results of our molecule, which took about 25 minutes to run, which is approximately 1.5 minutes for every bond that was broken. We can see a variety of different bond types, with the lowest energy bond dissociations being those of the carbon-hydrogen bonds next to the aromatic ring. The highest energy bonds are those of the aromatic carbon-hydrogens.