Professor Edward Piers passed away on July 18, 2010. He left a legacy of scholarly contribution to synthetic organic chemistry. While there have been a few obituaries that have adequately represented his life, this account is a very personal one that reflects how Ed influenced me, first when I was an undergraduate at UBC, and later as an assistant professor in Chemistry.
His scholarship and contributions to the chemical enterprise. Ed was an intellectually rigorous and scholarly person, and these traits are reflected best in his contributions to the chemical literature. Here are my favorites of his papers—in my opinion, the Edward Piers 'essentials'.
• Piers, E.; Waal, W. D.; Britton, R. W. "Stereoselective Total Synthesis of (+/-)-Seychellene" J. Am. Chem. Soc. 1971, 93, 5113. The highlight of his early career and "the paper that got me tenure", as Ed described it. This work showcases the use of substrate stereocontrol using a cis-decalin topology. This synthesis was taught to me by Larry Weiler at UBC, and eventually I taught the same course and also used this work. It is a good starter synthesis for undergraduates who have had second-year organic chemistry. Ed had commented that these graduate students at the time mix- and matched and worked on several overlapping total synthesis research problems at the same time, with little administrative organization on his part. They traded turns doing forefront chemistry, bringing up material and alternated running specific steps. "It was a strange way to organize it, but everything just seemed to click." was Ed's comment.
• Piers, E.; Ruediger, E. H. "Seven-membered ring annelation via Cope rearrangement of b-(2-vinylcyclopropyl)-a,b-unsaturated ketones: a new synthesis of (±)-b-Himachalene" J. Chem. Soc., Chem. Comm. 1979, 166. Piers, E.; Ruediger, E. H. "Preparation and Thermal Rearrangement of trans-3-[1-methyl-2-(2-methyl-1-propenyl)cyclopropyl]-2-cyclohexen-1-one. A Synthesis of (±)-b-Himachalene Can J. Chem. 1983, 61, 1239. In the titles of these papers you can see hints of the old-timey nomenclature stickler that he was. This synthesis has highlights in the preparation of substituted cyclopropylcopper reagents in a diastereoselective manner, and the use of a divinylcyclopropane rearrangement as a seven-membered ring annulation strategy.
• Piers, E.; Karunratne, V. “Annulation via donor-acceptor reagents. An efficient total synthesis of (±)-D-9(12)-Capnellene Can. J. Chem. 1984, 62, 629. Piers, E.; Karunartne, V. "Organotin-Based Bifunctional Reagents-4-Chloro-2-Lithio-1-Butene and Related Substrances-Methylenecyclopentane Annulations-Total Synthesis of (±)-D-9(12)-Capnellene" Tetrahedron, 1989, 45, 1089. He was meticulous in his approach to writing chemical descriptors: "Reagents do not react with a carbonyl, they react with a carbonyl function.", he'd tell me over coffee, or "Reactions occur on alkenyl halides, not on vinyl halides.". Precision was the order of the day. These papers are important as they highlight his "bifunctional reagent" concept. Most of his papers or student's thesis began with a retron-based synthetic approach, with a corresponding description of a newly conceived functionalized organotin or organic halide derivative that would serve as a new annulation reagent.
• Piers, E.; Marais, P. C. "A New 5-Membered Ring Annulation Method Based on Pd(0)-Catalyzed Intramolecular Coupling of Vinyl Iodide and Enolate Anion Functions" J. Org. Chem. 1990, 55, 3454. This work is important to me because it represents one of the first examples of a cross-coupling reaction between an Csp2-halide and a simple enolate. Other workers (Ihara, Hartwig) have followed up to make important contributions in this area but, in my opinion, Ed's work is not appropriately recognized.
• Piers, E.; Friesen, R. W.; Keay, B. A. "Intramolecular Palladium(0)-Catalyzed Coupling of Enol Triflate and Vinylstannate Functions-New Annulation Sequences Leading to Bicyclic Systems" Tetrahedron 1991, 47, 4555. Piers, E.; Friesen, R. W. "Annulations Leading to Diene Systems-Total Syntheses of the Dolastane-Type Diterpenoids (±)-(5S,12R,14S)-Dolasta-1(15),7,9-trien-14-ol and (±)-Amijtrienol" Can. J. Chem. 1992, 70, 1204. Ed's group was among the first to carry out an intramolecular Stille coupling, and this work emphasizes his interest in bifunctional reagents. The majority of Ed's work between 1969 and 1985 was published in the Canadian Journal of Chemistry. "I published there for nationalistic reasons; I thought it was the best way to support chemistry in Canada," Ed commented to me more than once.
• Piers, E.; Wong, T. "Copper(I) Chloride-Mediated Intramolecular Coupling of Vinyltrimethylstannane and Vinyl Halide Functions" J. Org. Chem. 1993, 58, 3609. Piers, E.; Romero, M. A. "Intramolecular CuCl-Mediated Oxidative Coupling and Alkenyltrimethylstannane Functions: An Effective Method for the Construction of Carbocyclic 1,3-Diene Systems" J. Am. Chem. Soc. 1996, 118, 1215. Piers, E.; McEachern, E. J.; Romero, M. A.; Gladstone, P. J. “Copper(I) chloride Mediated Oxidative Coupling of Alkenyltrialkylstannyl Functions: Efficient Stereocontrolled Syntheses of Uniquely Functionalized Conjugated Diene Systems” Can. J. Chem. 1997, 75, 694. These papers reflect his interest in both organotin and organocopper chemistry--areas in which he was recognized as a global leader. This work also clearly demonstrates important activation processes of organotin compounds using copper(I) chloride--interactions that were later recognized by E. J. Corey and Brian Stoltz in a oft-cited paper in J. Am. Chem. Soc. in 1999 on the accelerating properties of copper(I) chloride in Stille coupling reactions. Sadly, Ed's prior art has not often been cited.
• Piers, E.; Renaud, J.; Rettig, S. J. "Tetraquinane diterpenoids: Total Synthesis of (±)-Crinipellin B" Synthesis 1998, 590. Piers, E.; Renaud, J. "Total Synthesis of the tetraquinane diterpenoid (±)-Crinipellin B." J. Org. Chem. 1993, 58, 3609. This work was one of Ed's favorites, and was a project that he would often discuss when talking with department visitors. He liked this work especially because a number of different five membered ring annulations were developed. This is also one of the few instances one will see a germanium atom incorporated into an organic molecule!
I've skipped work that a Piers completist would include, especially his methodology studies dealing with the generation and use of organotin-containing copper reagents. To the field's detriment, Ed didn't write many (if any!) reviews or book chapters--"That's reliving the past. I have too many real papers to write." He told me often that one of his favorite times in his academic career took place at a Pacifichem meeting in Hawaii. He skipped all the talks and the assorted schmoozing and sat by the pool in the warm Oahu sun to write papers all day, five days in a row.
Ed as a teacher. This was weird and interesting for me as I interacted with him on both sides of the lecture podium. As a student, I found Professor Piers to be serious, intimidating, taciturn, no-nonsense. He was akin to Sam the Eagle from the Muppet Show. Unlike Sam the Eagle, he was also clear, thorough and expert. His notes defined clarity and precision. He was passionate, in his way, about undergraduate teaching. Like many of us, he was most interested in interacting with students who approached their academic studies with serious intent. Being a professor was not about the ego with him, just doing the job as effectively as he could. As a graduate student I was used to faculty members leaving the marking of an exam to a bunch of TA's, their contribution being occasional drop-ins during the marking period to observe. So I was initially shocked that Ed sat with the TA's and marked all session long. "It's what being a professor is about."
He was a gentle soul, an intensely private and humble man, not particularly interested in ego and celebrations of accomplishment. I think that he enjoyed the "moral authority", as he described it in another context, within our department that derived from his research success. Consequently, although it was not heard often, his voice within the department carried a great deal of weight among his colleagues. He was thoughtful and careful, and unwilling to rush to decision. Excellence and humbleness, in equal measure, were his measuring sticks. Few things irritated him more than self-absorbed individuals, and his use of the descriptor "operator" was, in essence, an epithet. I was fortunate to enjoy his company at coffee breaks on almost a daily basis. I told him often that of the people I'd met as a gentleman scholar he was the closest to Gilbert Stork—a complement in which he took particular pleasure. He had a warm, self-deprecating sense of humour, and could be cajoled just so. We spoke of his children and grandchildren often, and it was clear that he was as proud of them as anything he had accomplished in his academic career. His outside interests included golf (until his back gave way; he had a couple holes-in-one that he never tired of telling me about!), his family, his faith, photography and travel with his wife Shirley. I miss him every day.
Professor Gregory Dake, Department of Chemistry, University of British Columbia