JOURNAL OF CHEMICAL EDUCATION
PAUL PFEIFFER RALPH E. OESPER University of Cincinnati, Cindnnati, Ohio
PAUL PPEIFFER, director emeritus of the Chemisches tides, quiuhydrones and related compounds, and in adInstitut a t Bonn, creditably continued the Kekul& dition elucidated a series of combinations of medicinals. Anschiitz line, which made this university one of the He explained the constitution of nickel dimethylglyoxeminent centers of chemical instmction and research. ime, the copper complex in Fehling's solution, and tarHe was born on April 21, 1875, a t Elberfeld. After a tar emetic. He prepared the inner complex calcium year under KekulB, Pfeiffer transferred (1894) to Zur- and magnesium salts of special amino acids (Trilon A ich, where he took his doctorate in 1897 under Alfred and B), which are important with respect to water hardWerner.' Short periods were spent in Wilhelm Ost- ening. In 1915 he introduced the coordination conwald's laboratory in Leipzig and with Arthur Hantzsch cept into the theory of crystal structure. Among his purely organic fields of study, special note a t Wiirzburg. Dr. Pfeiffer habilitated a t Zurich in 1901, and in 1908 was promoted to an associate profes- should be made of the experiments aimed a t clearing up sorship in theoretical chemistry. He was called to the constitution of brasilin and hematoxylin; his conhead the department a t Rostock in 1916, and in 1919 ex- tributions to the theory of the betaiues; his iuvestiga, changed this post for a similar one a t Karlsrnhe. He tions of the autoxidation phenomena among the anils of indandioue; and the synthesis of the hitherto unknown IS resucceeded Richard Anschiitz a t Bonn in 1922. H' tiremeut in 1947 did not close his active career; he still p-chromanone. On the basis of complex chemistry, he developed a very simple procedure for the determinadelivers lectures and conducts laboratory researches. Professor Pfeiffer's scientific activities have been con- tion of the relative configuration of the natural a-amino cerned especially with problems of complex chemistry. acids, and i t turned out that, with respect to its configHe discovered the isomerism phenomena in the complex uration, glucosamiue is not related to the natural acompounds of chromium and developed the theory of amino acids. Professor Pfeiffer is the author of two widely known additive salt formation. He made extensive advances toward clarifying the constitution of halochromic com- books: "Organische Molekiilverbindungen" (1922, secpounds, and proved the existence of isomeric salts (col- ond edition 1927); and revision of A. Werner's orless and colored) in the case of aminoltetones. He "Neuere Anschauungen auf dem Gebiet der anorganalso studied the preparation and constitution of the ischen Chemie" (1923). nnubral salt com~oundsof amino acids and U O ~ ~ D ~ D - Besides honorarv deerees from Karlsmhe (1925) and
