HSP Application note #36
Hansen Solubility Parameter (HSP) and MicroWave
HSPiP Team Senior Developer, Dr. Hiroshi Yamamoto
Congratulation on Nobel Prize for Suzuki-Coupling Reaction!!
MicroWave heating is one of the most attractive heating method and begin to use at organic synthesis area. Some reaction speed increase dramatically. So this technique is very important in Green Chemistry area.
But some reaction does not accelerate at all.
And try and error experiment have done.
I got Dielectric Loss data for several solvent.
it is said, Dielectric Loss is large, that molecule absorb MW very well.
We have a lot of Dielectric constant experimental data for solvent.
But, dielectric constant and dielectric loss relation ship is not clear.
And for organic synthesis reagents’ dielectric loss is so hard to obtain.
So, we try to build QSPR model for predict Dielectric Loss with using HSP value.
Hansen Solubility Parameters (HSP)
Hansen Solubility Parameters(HSP) were developed by Charles M. Hansen as a way of predicting if one material will dissolve in another and form a solution. They are based on the idea that "like dissolves like" where one molecule is defined as being 'like' another if it bonds to itself in a similar way.
What can perhaps be surprising is that one can assign HSP to so many different things. Gases like carbon dioxide, solids like carbon-60, sugar, and biological materials like human skin, depot fat, DNA, and even some proteins all have HSP. The list can be continued with drugs, polymers, plasticizers, and in fact any organic material and even many inorganic materials like salts. The only requirement for an experimental confirmation is that the material must behave differently in a sufficient number of test solvents upon contact.
The result is very good except DMF and Formic Acid.
Formic acid make dimmer. DMF make hydrogen bonding network. So there is some exception, but we can predict dielectric loss with HSP.
Then we want to know which term work how.
dP is the polarity term, and we know that has correlation with dielectric constant.
But what we want to know is dielectric loss and not dielectric constant.
We also got the data of the achieved temperature after 1 min. exposure of MW.
|1minute radiation of MicroWave Achieved temperature|
We made the prediction scheme for achieved temperature from HSP
From this result, we believe, (2*dP+dH)*Volume*dD is the best fitting Index for absorbing MicroWave. You can get these number for all molecule(nonelectrite) if you use HSPiP.
If you want to know how to draw molecules, please refer to Power Tools applications.
HSPiP(Hansen Solubility Parameters in Practice)
The first edition of HSPiP that appeared in November, 2008, greatly enhanced the usefulness of the Hansen solubility parameters (HSP).
The HSP values of over 1200++ chemicals and 500 polymers are provided in convenient electronic format and have been revised and updated using the latest data sources in the second edition (March, 2009).
A third edition of the HSPiP appeared in March, 2010. There are now 10,000 compounds in the HSP file which also includes data on density, melting point, boiling point, critical parameters, Antoine constants and much more. The user is able to carry out many different sorts of optimisations of solubility, evaporation, diffusion, adhesion, create their own datasets (automatically if required) and explore the huge range of applications for HSP in coatings, paints, nanoparticles, cosmetics, pharma, organic photovoltaics and much more.
The 3rd Edition v3.1 was released on 12 December 2010. Current users can upgrade free (now v3.1.09) by downloading the latest .msi installer from http://hansen-solubility.com
The 4th Edition v4.0.x was released on 2 Jan. 2013. The Current users can upgrade with free charge.
2013.1.28 The Visual How to manual of HSPiP. You can understand what HSPiP can do.
If you have Smiles structure and HSPiP software, Y-MB function will calculate HSP immediately.
Smiles(Simplified Molecular Input Line Entry Syntax)
SMILES is a string obtained by printing the symbol nodes encountered in a depth-first tree traversal of a chemical graph.
Y-MB Properties Estimation
Y-MB break Smiles into correspponding Functional Groups and Estimate various Properties. These estimation schemes are come from Pirika technologies.
If you are doing experiment with MW, please check your yield with (2*dP+dH)*Volume*dD Index.
Suzuki coupling reaction got Nobel Prize of chemistry.
This reaction make Ar-Ar’ compounds with Pd catalyst with below mechanism.
I put this reaction in this micro wave article. There is very interesting episode.
Several years ago, there were a paper that said “Microwave assistant Suzuki-coupling need not Pd catalyst”. Finally this paper result find out wrong.
It need 20-50ppb Pd.
Even though, why Microwave can reduce catalyst amount so dramatically?
I want to think with HSP and
new index for MW heating (2*dP+dH)*Volume*dD
At first, Boron compound, dH is very large.
Our Index become 54600 and largest in the above table.
The other bromide, dP is very large and dP is multiply 2.0 so our index become 72200. Very very large.
Our index of water is around 30000, because water molecular size is very small.
So, we can say Suzuki coupling reaction reagents are easily absorb MicroWave.
And bromide, the largest vibration induced by MicroWave is between Phenyl ring and Br.
And maybe Boron compounds case, Phenyl ring and Boron bond will be vibrate violently.
And meet each other, make coupling.
With ordinal heating, every bond vibrate evenly. So it need catalyst that expand Br-Ph bond a little more. it is the reason that conventional heating needs much more catalyst.
So if you want to increase conversion with this reaction, you can easily check the effects of protection groups with HSPiP. If you use protection group that enlarge dP value, the Microwave will play effectively.
Anyway, HSPiP software can calculate HSP and volume, so it will very helpful for organic synthesis with micro wave.
Please try HSPiP!