Biographical Memoirs Volume 80 (2001) / Chapter Skim
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William Summer-Johnson
William Summer-Johnson
Pages 184-199
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From page 185... ...
Bill Johnson showocl himself to be a young man of many talents who spent much of his spare time in serious hobbies from constructing radios, an activity that he masterec! when barely a teenager, to cleveloping his consiclerable musical ability with enough enthusiasm to provide serious competition for his school work.
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From page 186... ...
The chemistry department was obviously quite impressed with Bill Johnson, en cl he was askocl to remain at Amherst an aciclitional year after graduation to teach organic chemistry. Not surprisingly, Johnson was acimittecl to the Ph.D.
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From page 187... ...
Car! Djerassi, Paul Flory, Henry Taube, Eugene Van Tamelen, en cl Harden McConnell, so that, even before Johnson relinquishecl his executive heacl responsibilities in ~ 969, the Stanforc!
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From page 188... ...
The few syntheses of natural products that had been recorded, such as those of camphor, cocaine, glucose, en cl hyciroquinine, were tributes to the brilliant experimental work en c! courage of the organic chemists who engaged in these difficult journeys, knowing that they wouIcl face complex en cl tedious separations of the various isomers to be expecter!
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From page 189... ...
Johnson later concluclecI, again on the basis of mechanistic considerations, that the clesirable bans bicyclic system shouIcl become the major product if he carrier! out his angular methylation scheme on a bicyclic system bearing a clouble bond parallel to the ring junction.
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From page 190... ...
chemistry as a powerful tool for the construction of polycyclic systems. At the time Johnson began to contemplate the possibility that cationic polyene cycTization might go beyond the realm of intriguing theoretical speculation, attempts at constructing complex organic structures reliecl almost entirely on base-catalyzed formation of enolate ions derived from carbonyl compounds, followed by their reaction with electrophilic carbon entities.
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From page 191... ...
that a single secondary allylic alcohol enantiomer, at the position which wouIcl eventually become the Il-oxygen center of a corticosteroicI, was able to survive the cycTization process en cl to incluce the correct enantioselectivity at all the relevant centers produced by the cyctization. An even more general contribution to synthesis methoclology followocl {ohnson's stucly of the a-alkoxy cations he sometimes usecl to initiate certain polyene cyclizations.
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From page 192... ...
Johnson shower! that careful analysis of the E-selectivity resulting from the Julia olefin synthesis of clisubstitutecl olefins strongly suggested that it might also leacl to selectivity in the construction of trisubstituted olefins, an even more clemancling problem.
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From page 193... ...
C~iMe3 /tOH Snc4: ~0% yid ~ WILLIAM S JOHNSON THE MAN It is, of course, not possible to derive Bill {ohnson's human qualities from the important contributions he macle to organic chemistry.
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From page 194... ...
Many, like Davicl Gutsche, Ralph Hirschmann, Hans Wynberg, Robert IrelancI, Richarc! Franck, James Marshall, John Keana, Kathlyn Parker, Martin Semmelhack, Paul Bartlett, Bruce Ganem, en cl Glenn Prestwich, became themselves leaclers in their field in academia, while many others, such as Barry Bloom, Raphael Pappo, Jacob Szmuszkovicz, John Pike, en cl I
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From page 195... ...
Cope awards, the Awarcl for Creative Research in Organic Chemistry, the Tetrahedron Prize for Creativity in Organic Chemistry, en c! the Nichols Mecial.
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From page 196... ...
S Tohnson's fascinating autobiographical account of his life in chemistry: A Fifty Year Love Affair with Chemistry.
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From page 197... ...
XVI. Racemic conessine, progesterone, cholesterol, and some related natural products.
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From page 198... ...
A new approach to steroid total synthesis. A non-enzymic biogeneticlike olefinic cyclization involving the stereospecific formation of five asymmetric centers.
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From page 199... ...
Daub. Corticoid synthesis via vinylic fluoride terminated biomimetic polyene cyclizations.~7.
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