Scholl

Scholle, Peter A. et al. (1983) Carbonate Depositional Environments, 708p, AAPG Memoir 33... 

BALLY - SCHOLL BenzanihreneSynthesis Synthesis of polycondensed aromatics from antraquinone and tnols. 

SCHOLL Polyaromatle synthesis Preparation of condensed polynuclear aromatics by Friedel-Crafts catalysts... 

One of the first reactions to be carried out in a molten salt (albeit at 270 °C) was the Scholl reaction. This involves the inter- or intramolecular coupling of two aromatic rings. A example of this reaction, in which 1-phenylpyrene was cyclized to indeno[l,2,3-cd]pyrene [26] is given in Scheme 5.1-7. A more elaborate version of the Scholl reaction is shown in Scheme 5.1-8 and involves bicyclization of an aromatic cumulene [27]. 

The Scholl reaction involves an overall oxidation of the coupled aromatic rings, yet there is no obvious oxidizing agent. This poses the question of what happens to the two hydrogen atoms that are produced in this reaction. It has been suggested that oxygen (air) may act as the oxidant, but this currently lacks confirmation [18]. 

Scheme 5.1-9 The Scholl reactions of two helicines. (a = NaCI/AICb (X(AICl3) = 0.69) at 140 °C).

Scholl and co-workers [91] performed the acylation of l-benzoylpyrene with 4-methylbenzoyl chloride in a NaCl/AlCl3 (X(A1C13) = 0.69) molten salt (110-120 °C). This gave l-ben2oyl-6-(4-methylben2oyl)-pyrene as the major product (Scheme 5.1-59). 

M. Scholl in Organic Conductors Fundamentals and Applications (Ed. J.P. Farges), Marcel Dekkcr, New York 1994, p. 539. 

R. Schlogl, in Progress in Intercalation Research (Eds. W. Miiller-Warmuth, R. Scholl-... 

Scholl et al (Refs 3 4) prepared the same compds by treating ketoximes (such as pina-colone) with nitrogen tetroxide, but he assigned them the structure R2C=N-N02 and called them nitrimines. One of the compds described by him in Ref 4, p 27 is a weak expl. It is the Ag salt of pinacolone-nitraminic acid which puffs off on rapid heating (this compd described below under List of Nitrimines ). Further work on... 

Scholl M, Trnka TM, Morgan JP, Grubbs RH (1999) Tetrahedron Lett 40 2247... 

Other coupling reactions were also employed to prepare poly(arylene etherjs. Polymerization of bis(aryloxy) monomers was demonstrated to occur in the presence of an Fe(III) chloride catalyst via a cation radical mechanism (Scholl reaction).134 This reaction also involves carbon-carbon bond formation and has been used to prepare soluble poly(ether sulfone)s, poly(ether ketone)s, and aromatic polyethers. 

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