Pioneering chemist John D. (Jack) Roberts of Caltech has passed away, having made it to the age of 98 (!) When I wrote The Chemistry Book a couple of years ago, I was amazed to find that he was still alive, I have to confess, but if I’d done a literature search on him I would have seen that he was publishing papers into an unusually advanced age as well. He was a huge influence on organic chemistry (particularly physical organic chemistry, the study of reaction rates and mechanisms), and was one of the key figures in realizing and applying the chemical applications of NMR spectroscopy. Among other discoveries, Roberts had the considerable nerve to advance the idea of benzyne as a reactive intermediate in 1954, showing by isotopic labeling experiments that there had to be symmetrical reactive intermediate in these systems.
If you’ve used chemical shifts and coupling constants to figure out the structure and/or conformation of a molecule by NMR, you owe a debt to Roberts. He and Linus Pauling persuaded Caltech to buy its first NMR machinery, which was, in fact, the first commercial NMR machine at a US university. (Pauling had, some years before, already told some of the NMR pioneers in chemistry not to listen to the physicists who were saying that it would probably be useless for chemical purposes). This is covered well in Roberts’ (out of print) autobiography, and you can read some about the early days in this interview at the American Institute of Physics (oddly enough, with an interviewer who seems to know no chemistry or physics).
He’s also well known for having more or less forced Caltech’s chemistry department to admit the university’s first female graduate student (Dorothy Ann Semenow), when he moved his group there from MIT. Roberts is indelibly associated with Caltech, having held many positions there over the decades (some at the same time), although he got his degree from UCLA and stayed influential there as well. He was famous for his wide range of interests in the field, his keen intelligence, and (as I’ve heard from first-hand accounts) being an extremely canny evaluator of other peoples’ work and ideas. Jack Roberts was one of the last people on Earth you’d want to try to slip any shoddy work past. Chemistry has now lost one of its last connections to an earlier era.