Fittig

Bromobenzene is a colourless liquid of b.p. 156°, and d, 1 50 it has a faint agreeable odour. The bromine atom, being directly joined to the benzene ring, is very inert, and the only common reactions in which it is split off from the ring are the Fittig reaction (p. 288) and the Grignard reagent (pp. 280-284). 

The Fittig Reaction, in which sodium reacts with a mixture of an aryl and an alkyl halide, forming the sodium halide and the corresponding hydrocarbon ... 

The Fittig Reaction is employed in the following preparation of ethylbenzene. 

Wurtz - Fittig reaction. The interaction of an aryl halide, alkyl hahde and sodium gives a reasonable yield of an alkyl aryl hydrocarbon, for example ... 

Two mechanisms have been proposed for the Wurtz reaction (compare Section III,7) and for the Wurtz-Fittig reaction. According to one, sodium reacts with the alkyl halide to produce a sodium halide and a free radical, which subsequently undergoes coupling, disproportionation, etc. ... 

Williamson synthesis Wohl-Ziegler reaction Wolff rearrangement Wolff Kishner reduction Wurtz reaction Wurtz-Fittig reaction... 

Wurster process Wurster salts Wurtz-Fittigcoupling Wurtz-Fittig reaction Wurtzite... 

Sodium and magnesium do not react with tetrachlorosilane at room temperature, but do so at elevated temperatures and ia the presence of polar aprotic solvents at moderately elevated temperatures. The Wurtz-Fittig coupling of organosilanes to form disilanes (168) and polysdanes (169) is usually accomphshed usiag molten sodium ia toluene or xylene. 

This type of reaction is sometimes considered a variant of the Wurt2-Fittig reaction. 

Methyl, ethyl and allyl acrylate were first prepared in 1873 by Caspary and Tollens, and of these materials the last was observed to polymerise. In 1880 Kahlbaum reported the polymerisation of methyl acrylate and at approximately the same time Fittig found that methacrylic acid and some of its derivatives readily polymerised. 

Poly-p-phenylene has been prepared in the laboratory by a variety of methods, including the condensation of p-dichlorobenzene using the Wurtz-Fittig reaction. Although the polymer has a good heat resistance, with decomposition... 

Cinnamic Acid.—The reaction, which takes place when an aldehyde (aliphatic or aromatic) acts on the sodium salt of an aliphatic acid in presence of the anhychide, is known as Perkin s reaction, and has a ery wide application. Accoid-ing to the result of Fittig s researches on the properties of the unsaturated acids described below, the reaction occurs in two steps. The aldeh) de forms first an additive compound with the acid, the aldehyde caibon attaching itself to the n-carbon ii.e.i nevt the carbovyl) of the acid. A saturated hydiOKy-acid is formed, which is stable, if the a-carbon is attached to only one atom of hydrogen, as in the case of isobutync acid,... 

The coupling of alkyl halides 1 upon treatment with a metal, e.g. elemental sodium, to yield symmetrical alkanes 2, is called the Wurtz reaction. Aryl alkanes can be prepared by the Wurtz-Fittig reaction, i.e. the coupling of aryl halides with alkyl halides. 

The synthetic applicability is rather limited, due to the various side-reactions observed, such as eliminations and rearrangement reactions. The attempted coupling of two different alkyl halides in order to obtain an unsymmetrical hydrocarbon, usually gives the desired product in only low yield. However the coupling reaction of an aryl halide with an alkyl halide upon treatment with a metal (the Wurtz-Fittig reaction) often proceeds with high yield. The coupling of two aryl halides usually does not occur under those conditions (see however below ) since the aryl halides are less reactive. 

Ludwig Wolff (1857-19191 was born in N6ustQdt/H8rdt, Germs ny, and received his Ph.D. from the University of Strasbourg working with Rudolf Fittig. He was professor of chemistry at the University of Jena. 

Another group of reactions can be classified as intermolecular dehalogenations or dehydrohalogenations, based on Wurtz-, Fittig-, Ullmann-, Grignard-, or Friedel-Crafts reactions. Thus, polyphenylenes may be obtained by polycondensations of p-dichlorobenzene in the presence of Na/K alloy83-85. ... 

Poly-(methacrylic acid) was prepared in 1880 by Fittig and Engel-horn. Mjoen separated the polymer by precipitation and attempted to determine its molecular weight by cryoscopic and ebullioscopic methods. He decided that his product, which he regarded as a colloid, was an octamer but reached no conclusions as to its constitution other than that it was an octabasic acid of the formula C24H4o(COOH)8. 

IV,1. n-Butylberkzene Wurtz - Fittig synthesis) IV,2. i o-Propylbenzene (cumene)... 

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