Finkelstein

D. B. Finkelstein and C. BeU, Biotechnology of Fi/amentous Fungi, Butterworth-Heinemaim, Stoneham, Mass., 1992. 

Finkelstein, D. B., and C. Ball, Biotechnology of Filamentous Fungi, But-terworth/Heinemann, Stoneham, Massachusetts, 1992. 

The expressions provide the limiting transition. When d Q for all j-phases, g rTf and the above expression transforms to the expression for a homogeneous sample. In case of the two-component powder, consisting of fluorescent and non-fluorescent par ticles, when size of the non-fluorescent par ticles d - Q, the above expression transforms to the expression for slurrylike substance (A.L. Finkelstein, T.N. Gunicheva, e. a. // X-Ray Spectrom. 1992. V. 21. p. 287-292). In case of the multicomponent powder with the equal size particles the expression transforms to the well-known Berry-Fumta-Rhodes formula. 

Finkelstein, A.V. Protein stmcture what is possible to predict now Curr. Opin. Struct. Biol. 7 60-71, 1997. 

When Pictet and Finkelstein condensed Aomoveratrylamine with /(omoveratroyl chloride and effected ring closure in the product, they obtained 3 4-dihydropapaverine (VII) but were unable to oxidise this to papaverine. This final step was achieved by Spath and Burger by the use of platinised asbestos at 200° in presence of air, and these authors found that tetrahydropapaverine (X) can be dehydrogenated to papaverine under similar conditions. 

A complete synthesis of laudanosine was effected by Pictet and Finkelstein by the condensation of omoveratrylamine (I) with homo-veratroyl chloride (II), giving omoveratroyl omoveratrylamine, which with phosphoric oxide undergoes cyclisation to 3 4-dihydropapaverine (III), which was converted into the methochloride and reduced to laudanosine (IV). 

LCAO with best exponent of 1.238 Finkelstein and Horowitz (1928) 2.354 106.8... 

These substances accelerate the reaction, and their effectiveness increases in the order given. This suggestion was questioned by Pocker, who found that the effects of such added substances were not directly proportional to their concentrations and could easily be explained by macro effects on the solvent character. He also found that common-ion effects were small in the reaction, the effect of added 1-methylpyridinium bromide was negligible, and that there was no evidence for surface catalysis on the walls of the vessel. There is an exact parallel between the relative rates of the Finkelstein reactions... 

The synthesis of alkyl halides from alkyl halides is called the Finkelstein reaction ... 

With primary alkyl halides 1 the Finkelstein reaction proceeds by a Sn2-mechanism. An alkali halide is used to deliver the nucleophilic halide anion ... 

Of preparative importance is the substitution of chloride or bromide or iodide, since the more reactive alkyl iodides are better substrates for further transformations. Alkyl iodides often are difficult to prepare directly, which is why the conversion of readily accessible chlorides or bromides via a Finkelstein reaction is often preferred. 

Secondary or tertiary alkyl halides are much less reactive. For example an alkyl dichloride with a primary and a secondary chloride substituent reacts selectively by exchange of the primary chloride. The reactivity with respect to the Finkelstein reaction is thus opposite to the reactivity for the hydrolysis of alkyl chlorides. For the Finkelstein reaction on secondary and tertiary substrates Lewis acids may be used," e.g. ZnCla, FeCls or MesAl. 

Alkyl fluorides can be prepared by the Finkelstein reaction. The fluoride anion is a bad leaving group the reverse reaction thus does not take place easily, and the equilibrium lies far to the right. As reagents potassium fluoride, silver fluoride or gaseous hydrogen fluoride may be used. 

FinkelStein reaction with sodium iodide is followed by acylation of heptane-3,5-dione to complete the synthesis of arildone (55). ... 

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