conkmpof~fyhi~tory
Columbia LEONARD edited University FINE by: New York. NY 10027
ERIC S. PROSKAUER
The Brief Career of a Prolific, Pioneering Physical Organic Chemist, Elliot Ritchie Alexander, Jr. Paul R. Jones University of New Hampshire, Durham, NH 03824
On the morning of the twenty-third of October, 1950, a small airplane plunged into the top of a mountain in southwestern Pennsylvania. As it crashed, the hright flames of life that danced in the hearts of Elliot Ritchie Alexander and his wife, Charlotte White Alexander, were instantly extinguished. These were no ordinary flames. In the four years that they had hurned on this campus they had illuminated the lives of hundreds among the students and the staff. They spread sparks of cheer and confidence among us, sparks that have kindled new fires in our hearts (I).
This citation, prepared by Nelson Leonard, Leonard Miller, and Harold Snyder, chemistry colleagues of Alexander, was read before the Liberal Arts Faculty a t Illinois shortly after Alexander's death in 1950. It raptures the pervading sense of respect for rhis young scientist's abilities and ac~o&~lishments and expresses the feeling of enormous loss with his untimely death. Yet no obituary or biographical account of E. R. Alexander, Jr., appeared in the New York Times or any chemistry publication at the time of his death, nor has any been written in the intervening 40 years up until the present when, had he lived, Alexander would have reached the age of retirement. Elliot Ritchie Alexander, Jr., was born on February 18, 1920, in Kansas City, Missouri. After elementary and high school training in Orlando, Florida, he earned the AB a t Swarthmore in 1941, majoring in chemistry. I t could be conjectured that young Alexander developed a scientific interest from his father, who held two patents for the preparation of concentrated citrus fruit extracts (2).As a graduate student a t Columbia, he received the MA in 1942 and completed the PhD in 1944, under the direction of Arthur C. Cope, who had a brief career a t Columbia during the war years before . eoine. to MIT. Alexander's research. involving . a svn. thetir method for simultaneous Knoevenagel condensation and hydrwrnation of the alkvlidene intermediate. led m a in Organic Syntheses ~ u b l i ~ h paper ed (3) and a (4).
Although Alexander had been accepted into the Air Force in 1944 and was enthusiastic to enlist, he became convinced that his efforts might be better directed toward chemical research. He embarked on national defense work a t du Pont in Wilmington and quickly developed what would he his characteristic approach to the solution of chemical problems: the mechanistic, physical organic approach. An example is his search for a polar, aprotic solvent. He settled on nitromethane, which led to a successful reaction. Alexander was awarded a Frank B. Jewett postdoctoral 882
Journal of Chemical Education
fellowship in October, 1945. With a leave of absence from du Pont, he was able to spend asemester each a t Harvard and a t the University of California-Berkeley, where he initiated research investigations into the mechanisms of aromatic sulfonation (5) and the Cannizzaro Reaction (6).At Harvard Alexander unofficially joined the group of young chemists who were to be greatly influenced by PaulD. Bartlett; among them was John D. Roberts, who shared a laboratory with Alexander. At the end of his fellowship year Alexander was hired as Instructor in Chemistry a t the University of Illinois. Ilir physical urganic approach io resesrrh was rcidrnt in his tenchiug and i n the direrting of graduate and undergraduate research students. They were introduced to writing mechanisms and to predicting the course of reactions by mechanistic reasoning. Besides continuing investigations into sulfonation (7,8) and the CanizzarroReaction (9),he began exploring mechanisms of several other well-known reactions by designing experiments in which he employed physical techniques such as cryoscopy, kinetics, and deuterium labeling. Evidence presented for assignment of structures included infrared and mass spectroscopy and X-ray powder patterns. The earliest paper published from work done solely a t Illi-
nois involved the deamination of arenediazonium salts in the presence of deuterated acid (10). In the following scant four years he published papers on deamination ( l l ) , the Leuckart Reaction (12), reductive amination (13), the Mannich Reaction (14), hydrogenolysis (15), dihenzoylfurazane oxide formation (16), a pyrrole-to-pyridine transformation (I7), and an improved method for the synthesis of ethyl 2,4-dimethyl3-furoate (18). Various investigations into the chemistry of acetals and ortho esters and their interconversions led to five nuhlications (19-23). ~ t r u c t u r e ~ e a c t i v irelationships ty were used.as evidence for vlausible mechanisms in several studies. In a series of three papers it was demonstrated that the acetate pyrolysis and Chugaev reaction proceed preferentially by syn elimination, as evidenced by the marked differences in rates for diastereomeric pairs (24-26). The different course of the ninacol rearrangement with meso- and racemic 2.3-butaned i d wns ratitmalized on the basis of preferred conformations of transition states during back-side attack ot'ths mieratine group (27). The stereo drawing! presented, althoughimbic uous, might be considered thf! forerunners of Newman projections. In one of two papers on the conjugate addition of Grignard reagents (28); i t was shown that the relative amount of 1,4- addition was comparable in cyclic and acylic enones. From these results it was concluded that a cylic transition state was relatively unimportant (29). Alexander was apparently the first to publish results on the isolation of optically active material where chirality was due solely to the presence of deuterium. He reported the formation of (-bdideuteriomenthane bv catalvtic svn addi. . " " tion of deuterium to (+)-2-menthenein apaper submitted in December. 1948 (30). He mav also have been the first or one of the first to use the term "asymmetric reduction" in connection with this catalytic transformation. In a second example he obtained (-)-3-deuterio-trans-menthane by reduction of (-)-menthy1 p-tosylate with lithium aluminum deuteride (31). In both cases the presence of the G D group was confirmed bv infrared svectroscow. In a study of t h e ~laise; ~earra&&nent with optically active starting material Alexander showed that the reaction proceeded with retention of optical activity (32). In this process, which Alexander called a "true asymmetric synthesis", control experiments were to exclude the possibility that the weak rotation was due to the presence of optically active impurities in the starting materials or products. While all this varied research was in progress, Alexander was busy writing a book on reaction mechanisms (33), the taneible outcome of a seminar he held with graduate studen.ts and srniors. In the 300 pages of this text;'rincipl~s of I m i r Rvurlions, Alexander depicted electron flow with curly arrows, an unfamiliar practice of the time. He covered surveys of carhonium ions, displacements, eliminations, carhanions, additions to C=C, C=O, and C=N bonds, formation and cleavage of ethers, esterification and hydrolysis, aromatic electrophilic substitution, diazonium reactions, the Wolff-Kishner reduction, and miscellaneous rearrangements such as the Claisen. Althoueh his choice of tonics mav have reflected his own interests,-he nevertheless Eited thk work of about 700 other authors besides himself. One of his students has noted that the text was the first book on organic mechanisms written from the standpoint of the organic chemist; another saw i t as filling a great need by making ionic reactions understandable and useful to organic chemists. I t became widely accepted as a textbook. The book, and
his 31 papers, in particular those on eliminations, are still being cited continually in present publications. Alexander exerted strong and lastine influence on his students, as several of them hive verifieduiu private correspondence. Five completed the PhD under Alexander's direction: Anton Mudrak and Elizabeth J. (Underhill) Harfenist in 1949; George R. Coraor in 1950; Sidney Baldwin in 1951; and Aaron B. Herrick in 1952. A. G. Pinkus earned an MS degree under Alexander in 1949. E. N. Marvell, although officially a PhD student of R. C.Fuson, undertook research projects outlined by Alexander in his last year of graduate school, while Fuson was onleave. The result was three publications (19-21). Undergraduate chemistry students coauthoring one or more papers with Alexander include R. E. Burge, H. M. Busch, D. C. Dittmer, M. R. Kintuer, R. W. Kluiher, J. D. McCollum, A. L. Misegades, T. M. Roder, F. W. Stone, G. L. Wehster, and R. B. Wildman; there may have been others who worked on research projects. Alexander's vibrant personality and endless energy were contaeious. A student in his sovhomore organic chemistry couriLdescribed him as follows:-'.~ewas the hest and most exciting lecturrr I had and undoubtedly influenced me very strong& to become an organic chemit%." Those who were associated with him found him eminently likable. He was never addressed as "Doctor" or "Professor". At Illinois i t was "Alex". In his brief stay a t du Pont he had been known as "Vitamin" because of his energy. The legacy he left behind is the result of his impact exerted in fewer than four years as a college faculty member. He symbolized a model approach t o physical organic chemistry, of his &ccessors. I t i s which was taken up by curious to project what would today he his accumulated contributions and influence, had he lived out the professional career that was so brief and yet so rich.
Literature Clted I. ~
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23. Alexander. E. R.: Buach. H. M.: Webster. G. L. J. Am. Chrm. S o r 1952. 74. 3173 Cwblished pm~humo&). 24. A1exsnder.E. R.;Mudrsk,A. J.Am. Chern.Sae 1950,72,181~1813. 25. A1eiander.E. R.;Mudrak,A. J Am. Chem.Soc. 1950.72.319P3198. 26. A1erander.E. R.:Mudrak,A. J. Am. Chom.Soc. 1951,73,5962. 27. Alexander. E.R.;Dittmar.D. C. J. Am. Chsm.Sac. 1951,73.166&1668. 28. Alexander, E. R.; McCollum, J. D.;Paul,D. E.J Am. Chern. Sor. 1950.72,4791-4792. 29. Alorsndcr,E. R.:Coraor, G. R.J.Am. Chem Soc. 1951.73.2721-2723. 30. Alexander, E.R.;Pinkus. A.G. J Am.Chem.Soc. 1949.71.1786-1789. 31. A1orander.E.R.J. Am. Chom.Soc. 1950.72.37963797. 32. Alexander. E. R.: Kluiber, R W. J. Am. Chem Soc. 1951, 73,430M306 (published pmthumously). 33. Alexander. E. R. Plinciplea ofIonic O~gonicReoctiow; Wiley: NsluYork, 1950.
Volume 84
Number 10
October 1987
883
