amphoteros

For those who go a step further

With the Fall semester around the corner, I am inclined to talk about chemistry education. Specifically, I will share my thoughts on a particular challenge synthetic organic chemistry has faced for years.

There are two types of students we encounter in chemistry classes: the ones who like to think and the ones who don’t. We want to attract those in the first category because they are the ones who will push the frontiers of our field. The question is: are we doing enough to ensure that the largest possible cross-section of bright students enters organic chemistry? I don’t think so.

We certainly do really well with “the naturals”. These kids have intuitive feel for chemistry and often possess a green thumb when it comes to lab work. They readily accept the bizarre “meta language” of organic chemistry and it quickly becomes second nature to them. But what do we do with those who are really intelligent, yet are not persuaded by the voodoo logic of organic chemistry? They are the ones who like to ask that inconvenient “next question”. For example, they are not satisfied to hear that the difference in electronegativity accounts for the fluorinated substrate (below) working well in the nucleophilic aromatic substitution and the chlorinated counterpart failing miserably. Such explanations are a bit too black and white for them and, from their perspective, more solid grounds are needed. I have encountered a number of such kids in my career and I can attest that the way organic chemistry is being taught is not suited for them. They might not have the natural intuition about what to do in a particular situation (e.g. which reducing agent should be used for a beta-keto ester…), but they are the ones who might enrich the field if we give them a chance. We just do not know because we lose these students to other, more quantitative, fields.

The question is: what can be done about this? Below is a lovely paper in the Journal of Chemical Education that I will definitely use in my classes. With the advent of sophisticated computing capabilities that can be run on a laptop and soon on a smartphone, there is a way of catering to those who ask deeper questions about chemical reactivity. In the particular case shown, it is a fairly straightforward natural bond orbital (NBO) analysis that clearly shows why the chlorinated substrate does not work. With more and more computational tools becoming accessible, it is worth thinking about introducing seamless connections between preparative organic reactivity and computational approaches. There are other examples of really enabling metrics, for instance Mayr’s nucleophiliciy scale (http://www.cup.uni-muenchen.de/oc/mayr/DBintro.html). We need more of this sort of stuff in organic chemistry.

http://pubs.acs.org/doi/abs/10.1021/ed5006344