Thiele, Johannes

Thus in 1899, Johannes Thiele extended his valence theory of double bonds to include colloids. Thiele suggested that in such materials as polystyrene the molecules of styrene were bound together merely by association of the double bonds. He referred to this association as "partial valence" (21). In 1901, Rohm concluded that the transformation of acrylic esters into polymers was from an "allotropic alteration" and not a chemical reaction (22). Schroeter, working with salicylides just as Kraut, Schiff, and Klepl before him, concluded that the tetrameric salicylide was formed by "external forces about the monomeric molecules", and that the chemical structures of the monomers were unaltered (23). Thus the association theory rapidly grew in popularity. 

When Herman Mark first evaluated the crystal structure of rubber (with E. A. Hauser) and cellulose (with J. R. Katz) in 1924 and 1925, it was generally accepted that these materials were low molecular weight or monomeric. The unusual properties of these substances, now known to be related to high molecular weight, were then attributed to aggolomeration or "association" of the low molecular weight precursors. A common explanation for the associations were secondary forces such as Johannes Thiele s partial valences. 

A truly impressionistic, or pointillist, scheme appears in the work of Johannes Thiele, to which we will return in chapter 5. Thiele attempted to explain anomalies in the behavior of butadiene, as well as benzene, by "floating" or "indeterminate" valences 83... 

By means of such assumptions, Werner was able to account for certain previously unexplained phenomena, such as the formation of tetrahydro-terephthalic acid by reduction of A dihydroterephthalic acid. It must be admitted, however, that this so-called 1,4 addition to conjugated double bonds was later explained in a more satisfactory manner by Johannes Thiele s theory of partial valences. 

BiBT94 Ingrid Biehl, Johannes Buchmann, Christoph Thiel Cryptographic protocols based on discrete logarithms in real-quadratic orders Crypto 94, LNCS 839, Springer-Verlag, BerUn 1994, 56-60. 

Figure 263 is from a rare pamphlet distributed at an 1886 meeting of the German Chemical Society that celebrated Kekule s structure work. The monkeys adopt two rapidly alternating structures (tails entwined and not entwined). The modem representations for benzene [dotted or solid circle in the hexagon — see Figure 71(b)] were contributed by Johannes Thiele in 1899 and Sir Robert Robinson in 1925. ... 

Just prior to the 20th century Johannes Thiele (1865-1918) studied additions to conjugated dienes and discovered a tendency toward 1,4-addition, for example, the bromination of 1,3-butadiene to form 1,4-dibromo-2-butene (part A in the accompanying figure). There were apparently unsatisfied "residuai vaiences" on carbons 1 and 4 of 1,3-butadiene that rendered these positions reactive. On the other hand, the "residuai vaiences" on carbons 2 and 3 of 1,3-butadiene were adjacent and "saturated each other" rendering these positions unreactive. The Lewis-Langmuir eiectron-pair structures, deveioped during the... 

Those studying colloids expanded their concepts until in 1899 Johannes Thiele extended his valence theory to double bonds. He suggested that the material, now known as polystju-ene, was merely styrene bound by association of its double bonds, he called this "partial valence". This... 

There is, nevertheless, a close connection between my Alma Mater, the University of Strasbourg and Hermann Staudinger indeed, here he discovered ketenes [3] in the course of his Habilitation under Johannes Thiele, at a time when this geographic region was part of an empire extending to the west of the river. Times of the past, and may they remain so forever, as we are now all Europeans ... 

Amino-l//-tetrazole (subsequently just 5-ATZ) was first synthesized by Johannes Thiele in 1892. He obtained this compound by cyclization of azidoformamidme in a boiling aqueous solutimi [28, 29]. 

Thiele, Friedrich Karl Johannes (1865-1918) French organic chemist. Thiele is best known for his concept of partial valence which he put forward in 1899. In order to explain the lack of reactivity of the benzene molecule Thiele postulated that when single and double bonds alternate then the overall bonding is less conducive to reactivity than purely double bonds. The concept of partial valence was not properly understood until the chemical bonding and valence of molecules such as benzene were explained in terms of quan-... 

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