Here is a shout out to my PhD student Sean Liew, whose paper recently came out in J. Org. Chem. Sean has been with us for about 2 years and, among other things, developed a great way to make vicinal diamines. One of the key control elements in this chemistry is attributed to the dimeric nature of aziridine aldehydes we have been working on. Below you see the transformation I refer to as well as Sean himself. Plus, I am showing a model Sean developed that accurately predicts the observed selectivity. The central feature of this chemistry is the hemiaminal that keeps the two monomers glued to each other for the duration of the transformation. The way the process operates is like this: the dimer partially dissociates, which allows it to interact with the incoming nucleophile. The said nucleophile is delivered to the nearby electrophile. In the present embodiment, we have boronate playing the role of the nucleophile and iminium ion acting as the electrophile. Towards the end of the reaction, the aziridine hemiaminal dissociates, releasing the product plus the monomer, which redimerizes. This is how we think about this chemistry. We are now trying to apply Sean’s reaction in a variety of contexts and the prospects are encouraging. Sean and I were asked by the J. Org. Chem. to come up with artwork so that the paper gets featured on the cover of the journal, which is cool. I am happy for Sean, although the deadline for the cover art is upon us. Why don’t I send Sean an annoying reminder email right about now?…
amphoteros 