On Tuesday, November 22, 2022 the web course LC-MS Method Validation was launched for the fifth time as a MOOC (Massive Online Open Course). There are 904 registered participants (the largest number ever in this course) from 104 countries, ranging from Sudan to Suriname and from Malaysia to Macedonia. Image on the left shows the countries where the participants come from.

This is a practice-oriented on-line course on validation of analytical methods, specifically using LC-MS as technique. The course introduces the main concepts and mathematical apparatus of validation, covers the most important method performance parameters and ways of estimating them. The LC-MS validation course is delivered by a team of 7 teachers, each with their own specific area of competence. This way it is expected to offer the best possible knowledge in all the different subtopics of analytical method validation.

The full set of course materials is accessible from the web page https://sisu.ut.ee/lcms_method_validation/. The course materials include videos, schemes, calculation files and numerous self-tests (among them also full-fledged calculation exercises). In order to pass the course, the registered participants have to take all tests and get higher than 50% score from each of them. These tests are available to registered participants via the Moodle e-learning platform. Participants who successfully pass the course will get a certificate from the University of Tartu.

In one week, on Nov 22, 2022 the online course LC-MS Method Validation will start!

Registration is still open (here). The course will run as a Massive Open On-line Course (MOOC) during Nov 22, 2022 – Feb 03, 2023.

This is a practice-oriented on-line course on validation of analytical methods, specifically using liquid chromatography-mass spectrometry (LC-MS) as technique, mostly (but not limited to) using the electrospray (ESI) ion source. The course will also be of interest to chromatography practitioners using other detector types. The course introduces the main concepts and mathematical apparatus of validation, covers the most important method performance parameters and ways of estimating them. More information about the course can be found in Course introduction page.

Participation in the course is free of charge. Receiving digital certificate (in the case of successful completion) is also free of charge. Printed certificate (to be sent by post) is available for a fee of 60 EUR. Registration is possible until the start of the course. The course material is available from the above address all the time and can be used via web by anyone who wishes to improve the knowledge and skills in analytical method validation (especially when using LC-ESI-MS).

On Aug 15, 2022 Ivo Leito gave a presentation Acidities of Fluorocompounds at the 20^th European Symposium on Fluorine Chemistry taking place in Berlin (Germany) during Aug 12-19, 2022.

Fluorination, especially polyfluorination is a powerful means for acidifying molecules. So, many fluorine-containing compounds are acidic (Scheme on the left) and some are remarkably strong acids, e.g. the well-known trifluoromethanesulfonic acid CF₃SO₃H or the bis(trifluoromethane)sulfonimide (CF₃SO₂)₂NH.

The first part of the presentation gave a brief overview of the acidity of molecules, expressed as pK_a values, acidity scales (pK_a scales) on the example of the acetonitrile pK_a scale and discussed two important pK_a measurement methods: UV-Vis and NMR spectrometry.

The second part of the presentation specifically addressed the relative pK_a measurement method based on ¹⁹F NMR for accurate measurement of pK_a values of fluorocompounds (Scheme on the right). The presentation demonstrated that ¹⁹F NMR has a number of advantages, compared to most other methods: accurate concentrations of acids not needed, method is tolerant to impurities in compounds, several compounds can be measured simultaneously, solvent or titrant signals do not hinder measurements and deuterated solvents are not needed. Using multiple relative measurements against several reference compounds with known acidities, it is possible to obtain highly reliable pKa values.

We were very pleased to learn today that the the Nobel Prize in Chemistry 2021 was awarded to Benjamin List (Max-Planck-Institut für Kohlenforschung, Mülheim an der Ruhr, Germany) and David W.C. MacMillan (Princeton University, USA) “for the development of asymmetric organocatalysis”!

The List group is world-famous for developing superacidic organocatalysts, enabling a very wide range of challenging transformations. We are happy that there is also a tiny contribution from our group to prof. List’s research: the acidities (expressed as pK_a values in acetonitrile of 1,2-dichloroethane) of some of their acid catalysts (1,1,3,3-Tetratriflylpropene and some chiral superacidic imides) have been measured in our lab. Recently we were happy to host people from the List group in our lab and they learned how to carry out pK_a measurements in nonaqueous solutions. The collaboration will continue.

Big congratulations to prof. List and to prof. MacMillan!

(Photo: The Nobel Prize committee)

In a recent account Design of Novel Uncharged Organic Superbases: Merging Basicity and Functionality. Acc. Chem. Res. 2021, 54, 3108-3123 four groups doing research at the forefront of superbase chemistry – IOCB (Czech Republic), Rudjer Boskovic Institute (Croatia), Philipps-Universität Marburg (Germany) and our group at University of Tartu – have joined forces in charting the direction for further developments of the whole organosuperbases area. What synthetic chemists need, are “non-ionic, metal-free superbases as chemically stable neutral organic compounds of moderate molecular weight, with intrinsically high thermodynamic basicity, adaptable kinetic basicity, and weak or tunable nucleophilicity at their basicity centres”. Such superbases would be are useful, being able to catalyze a number of reactions that are impossible otherwise.

The account demonstrates that just trying to achieve ever higher basicity is not the main challenge. Very high basicities have been demonstrated, both computationally and experimentally. Instead, the combination of high basicity with moderate molecular weight, ease of synthesis and stability is the key issue.

The account starts with the state of the art of neutral organic superbase research, theirs synthesis and basicity measurements, as well as computations and thereafter presents several examples of emerging organosuperbase families (see the Figure on the left) and discusses their synthesis, basicity and demonstrated, as well as potential applications.