In the preceding post, I discussed the reaction between mCPBA (meta-chloroperbenzoic acid) and cyclohexanone, resulting in Baeyer-Villiger oxidation via a tetrahedral intermediate (TI). Dan Singleton, in whose group the original KIE (kinetic isotope measurements) were made, has kindly pointed out on this blog that his was a mixed-phase reaction, and that mechanistic comparison with homogenous solutions may not be […]

I have blogged before about the mechanism of this classical oxidation reaction. Here I further explore computed models, and whether they match the observed kinetic isotope effects (KIE) obtained using the natural-abundance method described in the previous post.

My PhD thesis involved determining kinetic isotope effects (KIE) for aromatic electrophilic substitution reactions in an effort to learn more about the nature of the transition states involved.

I am on a mission to persuade my colleagues that the statistical analysis of crystal structures is a useful teaching tool.

As I have noted elsewhere, Gilbert N. Lewis wrote a famous paper entitled “the atom and the molecule“, the centenary of which is coming up. In a short and rarely commented upon remark, he speculates about the shared electron pair structure of acetylene,  R-X≡X-R (R=H, X=C). It could, he suggests, take up three forms.

A lunchtime conversation with a colleague had us both bemoaning the distorting influence on chemistry of bibliometrics, h-indices and journal impact factors, all very much a modern phenomenon of scientific publishing.

The Bürgi–Dunitz angle is one of those memes that most students of organic chemistry remember. It hypothesizes the geometry of attack of a nucleophile on a trigonal unsaturated (sp2) carbon in a molecule such as ketone, aldehyde, ester, and amide carbonyl.

Blogging in chemistry remains something of a niche activity, albeit with a variety of different styles. The most common is commentary or opinion on the scientific literature or conferencing, serving to highlight what their author considers interesting or important developments. There are even metajournals that aggregate such commentaries. The question therefore occasionally arises;

Allotropes are differing structural forms of the elements. The best known example is that of carbon, which comes as diamond and graphite, along with the relatively recently discovered fullerenes and now graphenes. Here I ponder whether any of the halogens can have allotropes.

Egon has reminded us that adoption of ORCID (Open researcher and collaborator ID) is gaining apace. It is a mechanism to disambiguate (a Wikipedia term!) contributions in the researcher community and to also remove much of the anonymity (where that is undesirable) that often lurks in social media sites.

The knowledge that substituents on a benzene ring direct an electrophile engaged in a ring substitution reaction according to whether they withdraw or donate electrons is very old. Introductory organic chemistry tells us that electron donating substituents promote the ortho and para positions over the meta.