Organic spectroscopy, the application of spectroscopic methods to determination of the structure of the molecules organic chemists are interested in, came of age during the Golden Sixties. The twin engines which lifted it to prominence were mass spectrometry (ms), which had been developed extensively in the nineteen-fifties when engineers analyzed the hydrocarbons present in oil; and nuclear magnetic resonance (nmr), which had been discovered in the immediate aftermath of World War II.
Organic spectroscopy arose out of a bleak, almost desertic landscape. In the early nineteen-fifties, available instrumental techniques were indirect only (dipolemetry, ultraviolet electronic spectra interpreted with the Woodward rules, infrared spectroscopy), limited to rather small or highly symmetrical molecules in the gas phase (electron diffraction, microwave spectrometry), or yet excruciatingly labor- and time-intensive (X-ray diffraction).
A major factor in the overwhelming success of organic spectrocopy was its close association with physical organic chemistry, then (1960s) at the zenith of its influence. It thrived in American departments of chemistry which were powerhouses of physical organic chemistry, such as UCLA, where Frank Anet interfaced with Saul Winstein and Donald Cram (which led to his discovery of the nuclear Overhauser effect); the University of Utah, where David M. Grant had, among his colleagues, Henry Eyring, Josef Michl, Peter Stang and Cheves Walling; Yale, where likewise Martin Saunders thrived in the company of Jerome A. Berson and William von Eggers Doering; MIT, where John S. Waugh was a colleague of C. Gardner Swain; not to mention cases in which the two personas coincided in a single person, such as John D. Roberts at Caltech or Gerhard Closs at the University of Chicago, the latter of whom promptly explained the brand-new phenomenon of chemically-induced dynamic nuclear polarization.
Nmr and ms quickly influenced the organic community due to a few outstanding books: for nmr, those by A. Abragam (1961), Pople, Schneider and Berstein (1959), J.D. Roberts (1959 and 1961), L.M. Jackman (1959); and, for ms, by K. Biemann (1962), C. Djerassi et al. (1964), and F.W. McLafferty (1966). The OCEANS conferences (later renamed ENC), held in the spring at the Mellon Institute in Pittsburgh, transferred leading edge research into routine laboratory practice. An informal monthly newsletter (Mellon NMR, subsequently TAMU NMR) complemented them.
Institutional policies governing the welcome to be extended to the new spectroscopies were diverse. German conservatism on the part of the ruling professors, who had been nurtured on the synthetic rather than the analytical side of organic chemistry, saw to it that organic spectroscopy was barred from chairs in the leading universities. The dominant American mentality was somewhat similar. The enormously influential chemistry department at Harvard University viewed nmr as an ancillary technique; the person in charge there was not deemed worthy of a tenured professorial rank. Accordingly, nmr experts rose to eminence only in schools training engineers, such as MIT, or in departments of chemistry rather remote from the Ivy League, such as Arizona, Florida, Stanford or SUNY at Stony Brook. Others found employment in government laboratories, such as the Jet Propulsion Laboratory in Pasadena or Livermore at Berkeley.
Moreover, granting agencies such as the National Science Foundation were initially short-sighted. Given the high capital expenditures, they encouraged setting-up universitywide or even regional centers to house instruments and technical staff, on the model of the contemporary computer centers, imposed likewise by the hugely costly mainframe computers.
Reinhardt is an especially skilled narrator and his recounting of the twists and turns of early nmr and ms, as applied to organic chemistry, is superb. The book is on the whole a fascinating account of the role of half-a-dozen leaders: Herb Gutowsky, Jack Roberts and Richard Ernst for nmr; Carl Djerassi, Klaus Biemann and Fred McLafferty for ms. To define a field by its leaders is akin to viewing a mountain range only in terms of its highest peaks. It leads the historian to miss out on the substance. It behooves one to study, not only the careers of the leaders of the discipline or sub-discipline, more so the achievements of scientists who did not enjoy the limelighht to a similar extent. There is more to be learned from the latter than from the former, it may safely be contended. Numbers alone see to it. Reinhardt collected his information from interviews with the six above-named scientists. Such an approach has archival value, but it lacks in significance. Historians dislike such accounts, deservedly, because such interviews are self-serving, lack cross-checks, omit the context, and conflict with the narratives they are trained to construct. There were two sides to the story, the need organic chemists had for organic spectroscopy, and the changes the new methodologies induced in chemistry. Reinhardt’s book is eloquent about the former and silent about the latter.
And yet! The enrichment of organic chemistry by nmr was many-splendored. Conformational analysis took off in a big way. Fluxional molecules, starting with bullvalene as a seminal case, presented chemists with a fascinating new aspect of molecular reality. Organo-metallic chemistry blossomed enormously on the strength of multinuclear magnetic resonance. Nmr took over from existing physical methods, too. For instance, it replaced polarimetry in determinations of enantiomeric excesses in reactions.
The story is well worth telling. Reinhardt’s book is a good start in that direction.
Pierre Laszlo is emeritus professor of chemistry at Ecole polytechnique, Palaiseau, France and University of Liège, Belgium. Together with Peter J. Stang, he authored Organic Spectroscopy (Harper and Row, New York, 1971). He taught a course of instrumental analysis at Cornell, jointly with Fred W. McLafferty. His current interests combine history of chemistry and science writing.
The background: Paul Lauterbur as a pioneer.
Rise of quantum chemistry: QCPE – Coulson’s book – Streitwieser’s book – Jaffe & Orchin’s book.
Reinhardt’s book requires careful picking and choosing on the part of the reader.
(His controversial claims are oddly mixed: some are both surprising and likely true, while others are simply silly: na?)