Woodward's Unfinished Work

Stacked neatly in a cardboard box, Eric Woodward has exactly 699 pages of decades-old notes written by his father. Most people would describe a box of their parents’ old notes as little more than sentimental ephemera or even junk bound for the trash bin. But most people aren’t the children of Robert Burns Woodward, the acclaimed Harvard University chemistry professor and 1965 Nobel Laureate in Chemistry.

Many of the pages have yellowed with age, but to those in the chemical community, the contents of that modest cardboard box are a veritable treasure trove. They are Woodward’s notes on conducting materials—a project that he clearly spent a considerable amount of time thinking about but that resulted in only two papers (Proc. R. Soc. Lond. A 1979, 366, 23; J. Am. Chem. Soc. 1981, 103, 1540), the latter of which was published post humously.

Now, more than 30 years after his death, a selection of Woodward’s ideas in this area are being made public in a perspective article in Tetrahedron (DOI: 10.1016/j.tet.2011.05.004). The paper features two dozen drawings and notes from the famed organic chemist, best known for his total syntheses of natural products such as chlorophyll and strychnine and his theoretical work on pericyclic reactions.

“In the last three years of his life, R. B. Woodward was gripped by the idea of designing and synthesizing an organic superconductor,” writes Roald Hoffmann, a Cornell University professor who collaborated with Woodward on some of the work, in a preface to the publication. “The evidence to that creative obsession (and I use the word in its most positive sense) is to be found in the hundreds of meticulous drawings of molecules he left behind at his untimely death in 1979.” At that time, Hoffmann notes, organic conducting materials and organic superconductors were hot topics, but “no one had yet made an organic superconductor of any transition temperature of note.”

Although it’s difficult to pin down precisely when Woodward began to think about organic conductors and superconductors—for none of the 699 pages bears a date—Eric Woodward believes that his father’s interest in the area emerged as early as 1967 or 1968.

He vividly recalls one evening when he was a teenager: “My father arrived punctually at home at 6:25 every night for dinner. One night we sat down and he said, ‘I’ve had an inspiration. I think I can make a room-temperature superconductor.’ He described how that would be a material that loses no energy as it conducts electricity over large distances and how that would change the world,” Eric remembers. “He rarely would say anything about chemistry, but this day he was particularly inspired.”

To skip to the end of the story, little came of Woodward’s inspiration in the area of superconductivity and conducting materials. He tried to get his team at the Woodward Research Institute in Basel to work on the project, his son recalls, but was largely frustrated by the results, or lack thereof.

When Woodward died in 1979, his two youngest children, Eric and Crystal, were tasked with cleaning out his office at Harvard. There they found a stack of notes 8 inches thick about conducting materials, written on everything from photocopy paper to blue paper to hotel stationery.

“One of the big challenges after my father died was figuring out what do with all his chemical drawings,” Crystal says. “They’re intellectual and scientifically full of the thought process, and they’re artistically very beauti ful.”

Most of Woodward’s notes went to the Harvard University Archives. But the notes on conducting materials were never part of a Harvard research effort, Eric says, so he and his sister kept them. “I was hoping there were still some unexplored nuggets of brilliance in this work that hadn’t been realized yet,” he says, but neither of them was a chemist, so they couldn’t be sure.

“It didn’t seem that we were sitting on a gold mine, but we didn’t know,” Crystal says.

So they turned to Robert M. Williams for advice. Williams, now a chemistry professor at Colorado State University, was at the time a postdoc in the Woodward group and a close family friend. “I looked at these notes—sometime in 1979—and I was blown away by the sheer magnitude and the depth at which he was thinking about conducting materials,” Williams remembers.

But the notes were far from Williams’ area of expertise. He told Eric and Crystal that even though he thought they were probably of great historical significance, they were unlikely to contain anything of commercial value.

And then, nothing happened with the notes for quite a number of years, a fact that Eric says had “much more to do with inertia than anything else. If we really felt there was commercial value in the notes, we would have been pushing to get some commercial result,” he explains.

Because Hoffmann had collaborated with Woodward on the conducting materials research, Eric and Crystal also sought out his thoughts on the commercial viability of the ideas in the notes. “Roald Hoffmann’s opinion was a major part in my not pursuing other people to take on the research,” Eric says.

“My opinion is that there is nothing patentable in there,” Hoffmann tells C&EN, “but I speak from a background of not owning a single patent.”

Still, Williams remembered the notes and would, year after year, pester Eric to find a way to preserve them for the chemical community.

By 2000, the paper was starting to deteriorate, and Williams remembers telling Eric, “In the future, these notes may be viewed as a very interesting historical footnote to your dad’s career, but if the notes decompose into a pile of confetti dust in the box you’ve been keeping them in, they’re going to be worth nothing to anybody.”

The Woodwards finally agreed that the notes should be digitally preserved, and Williams paid Eric’s two daughters, then 15 and 12, to digitally scan each of the 699 pages. Williams also asked Eric and Crystal if he might seek out an author to put together a paper on the ideas contained in the notes. Ideally, he says, he was looking for someone who had been a student of Woodward’s, to alleviate any concerns the Woodward children had about someone stealing their father’s ideas.

At the suggestion of then Tetrahedron editor and Yale University chemistry professor Harry H. Wasserman, Williams approached Michael P. Cava, a chemistry professor at the University of Alabama who had worked as a postdoc with Woodward on the synthesis of strychnine. Independent of Woodward, Cava’s research focus as a principal investigator had moved into the arena of organic conducting materials. Along with his long-term research associate M. V. Lakshmikantham, Cava sifted through Woodward’s notes and pulled together some analysis of Woodward’s ideas in this area.

The writing and editing of the paper took longer than anyone imagined, Williams says, and, sadly, both Cava and Lak shmikantham passed away before it was submitted for publication.

The paper focuses largely on Woodward’s ideas about poly(thiazyl) systems, (SN)_x, and their isoelectronic organic variants (SCR)_x. Hoffmann believes that Woodward was initially inspired by some of the papers on poly(thiazyl) systems that were published in the 1970s. “I think Woodward also read William Little’s simple account of how the interaction of electronic motions and molecular vibrations might create superconductivity,” he tells C&EN. Although there were physicists and a few chemists working in the area, Woodward thought his expertise in organic chemistry could bring new insight to the field, Hoffmann adds.

Little’s paper in Scientific American (1965, 212, 21) strongly influenced many working in the field of organic conducting materials, notes Fred Wudl, a chemistry professor at the University of California, Santa Barbara, who studies organic electronics and did postdoctoral research with Woodward in the late 1960s. Like Cava, Wudl’s interest in organic electronics developed independently of Wood ward’s.

The new Tetrahedron perspective “is an unusual glimpse into Woodward’s thinking at the height of the pursuit for organic superconductors by chemists and physicists,” says Wudl, who notes that Woodward’s ideas were quite clever for the time.

“In commenting about this manuscript, one cannot apply the current concepts and mechanisms that have evolved since Woodward’s interest in the area,” Wudl notes. “It is, however, clear that he had very similar ideas to those of the few organic, inorganic, and physical chemists who were researching in the field at the time, and he would very likely have eventually developed novel conjugated polymers and two-dimensional solids with unusual electronic properties.”

The Tetrahedron perspective only hints at how deeply Woodward was thinking about conducting materials, according to Williams. “Cava commented on only 10 to 15% of the actual structural content in the notes,” he says. “Woodward started with ideas about nitrogen- and sulfur-containing heterocycles and other polymers, and then his thoughts drifted to metal-containing polymers and metal-containing lattices and then mixtures of heterocycles and metals and all types of things.”

“He was thinking at top creativity level,” Hoffmann adds. “That’s what those hundreds of blue and yellow pages testify to.” But Hoffmann also thinks the notes point toward Woodward’s desire to stake out new territory.

“In a broader sense, the question I think could be asked: Was Woodward looking for a different direction to exercise his well-developed and exhibited talent for synthesis other than making natural products?” Hoffmann wonders. “Stepping outside natural products was a natural thing for him. He was interested in making theoretically interesting molecules,” Hoffmann says, pointing to Woodward’s role in the discovery of ferrocene and his work on the 7-norbornadienyl cation with University of California, Los Angeles, chemistry professor Saul Winstein.

Still, such interests didn’t always translate to work at the bench. “I had hints that he had difficulty convincing Harvard graduate students and postdocs to work on the project,” Hoffmann says of Woodward’s ideas on organic conducting materials.

Jeffrey I. Seeman, a chemical historian at the University of Richmond who has been studying Woodward, says, “Woodward made and saved pages and pages of handwritten notes on major research projects such as orbital symmetry, but 699 extant pages on organic conducting materials is extraordinary, even for Woodward.” He adds, “What is interesting, even perplexing, is the extent to which there are so many notes and apparently so little experimental work done.”

But it’s difficult to assess just how hard Woodward tried to convince his graduate students and postdocs at Harvard to work on the project.

David Wenkert, now a professor of physiology at Michigan State University, was one such graduate student. Part of Wenkert’s doctoral thesis research was published in Woodward’s posthumous JACS paper. That paper described a novel heterocycle that was synthesized as a side product while the researchers were trying to prepare some of the polymers Woodward was interested in.

Wenkert recalls visiting Woodward one day in either 1976 or 1977 to speak with him about problems he was having on another project. “He brought up this idea that he had just come up with as a project for me to work on,” Wenkert remembers. “He started jotting down for me some of the initial ideas he had and the theory behind them for conductors that had the potential to be superconductors,” he says. “He had asked me not to talk to anybody about it, and I never have.”

When Wenkert returned to Woodward’s office a few weeks later, he saw that Woodward’s thoughts had expanded to 2-D polymers that stemmed from the same idea. Around that time, he recalls, “people suddenly saw Woodward in the library at night. They didn’t know what was up. But I kind of figured that he was working on this project.”

Aside from the work that was ultimately published in JACS, Wenkert declined to do research on the conducting polymers. “Practically, I didn’t think this was a project I could work on and get a Ph.D. thesis out of, given my lack of experience in polymer chemistry,” he says.

Still, Wenkert says, “it was just incredible for me to be able to see the beginning of an idea of his that he then developed. I thought it was amazing. To me it was the most intellectually stimulating interaction that I ever had with him. I still have the notes somewhere in my basement.”

As for the 699 pages of notes in the cardboard box, the future is uncertain. Now that the notes have been scanned, it’s theoretically possible they could be made available to the public, but both Eric and Crystal Woodward say there are no plans to do so at the moment. “But no plans not to either,” Eric says. “In other words, it’s an open question.”

Both Williams and Hoffmann hope the scanned notes will someday find a home on the Web where everyone will have access to them, either through the Harvard University Archives, the Chemical Heritage Foundation, or some other entity. “My wish is that they’d become a permanent, accessible treasure for the chemical community,” Williams says.

For now, the paper will have to suffice for those wishing to get a glimpse of Woodward’s unfinished work in organic conducting materials. “I think the most important thing is just to get some of the visual images out there so the chemical community can see what Woodward was doing in his last days,” Williams remarks.

“I think this is incredibly interesting as an insight into the thought process. We just don’t see this very often,” Hoffmann adds. “It’s great that the notes are finally seeing the light of day. I think ultimately Woodward believed that the true achievements of this world are the gifts of knowledge we give to other people.”