Homoaromaticity is a special case of aromaticity in which π-conjugation is interrupted by a single sp3 hybridized carbon atom (it is sometimes referred to as a suspended π-bond with no underlying σ-foundation). But consider the carbene shown below. This example comes from a recently published article which was highlighted on Steve Bachrach’s blog.

I reminisced about the wonderfully naive but exciting Web-period of 1993-1994. This introduced the server-log analysis to us for the first time, and hits-on-a-web-page.

In 1993-1994, when the Web (synonymous in most minds now with the Internet) was still young, the pace of progress was so rapid that some wag worked out that one “web-year” was like a dog-year, worth about 7 years of normal human time. So in this respect, 1994 is now some 133 web-years ago.

This is a continuation of the discussion started on Steve Bachrach’s blog about a molecule with a very short H…H interaction involving two Si-H groups with enforced proximity. It had been inferred from the X-ray structure that the H…H distance was in the region of 1.50Å. It’s that cis-butene all over again!

In the two-publisher model I proposed a post or so back, I showed an example of how data can be incorporated (transcluded) into the story narrative of a scientific article, with both that story and the data each having their own independently citable reference (using a doi for the citation). Here I take it a step […]

The best known example of the gauche effect is 1,2-difluoroethane, which exhibits a relatively small preference of ~0.5 kcal/mol for this conformer over the anti orientation, which is also a minimum. But FSSF, which I discussed in the previous post, beats this hands down!

Paul Schleyer sent me an email about a pattern he had spotted, between my post on F3SSF and some work he and Michael Mauksch had done 13 years ago with the intriguing title “Demonstration of Chiral Enantiomerization in a Four-Atom Molecule“. Let me explain the connection, but also to follow-up further on what I discovered in […]

I do go on rather a lot about enabling or hyper-activating data. So do others. Why is sharing data important?

Andy Extance at the Chemistry World blog has picked up on a fascinating article on the dimer of SF2. This molecule has three F atoms on one S, and only one on the other; FSSF3. But all four S-F bonds are of different length.

According to Herges, the mechanism of single-step (concerted) reactions can be divided into three basic types; linear (e.g. substitution, elimination etc), pericyclic (e.g. Diels Alder) and a third much rarer, and hence very often overlooked type that was named coarctate.

The concept of a “hidden intermediate” in a reaction pathway has been promoted by Dieter Cremer and much invoked on this blog. When I used this term in a recent article of ours, a referee tried to object, saying it was not in common use in chemistry. The term clearly has an image problem.