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Phenylcyanoacetic acid

Silipo and Hansch 77) have developed correlation equations for the formation of a-cyclodextrin-substituted phenyl acetate complexes (Eq. 13), a-cyclodextrin-RCOO complexes (Eq. 14), and P-cyclodextrin-substituted phenylcyanoacetic acid anion complexes (Eq. 15). [Pg.72]

A few examples have been reported in which no steric parameter is involved in the correlation analysis of cyclodextrin catalysis. Straub and Bender 108) showed that the maximal catalytic rate constant, k2, for the (5-cyclodextrin-catalyzed decarboxylation of substituted phenylcyanoacetic acid anions (J) is correlated simply by the Hammett a parameter. [Pg.85]

Kinetic Parameters for the Cycloheptaamylose-Catalyzed Decarboxylation of Phenylcyanoacetic acid anions at pH 8.6 and 60.4° ... [Pg.242]

The results presented by Cramer and Kampe are amplified by the data in Table XII which correspond to a recent investigation of the cyclohepta-amylose-catalyzed decarboxylation of a series of substituted phenylcyanoacetic acid anions (Straub and Bender, 1972). These data differ strikingly... [Pg.243]

Fig. 8. Hammett pa correlations for the cycloheptaamylose-catalyzed ( ) and the uncatalyzed (O) decarboxylation of phenylcyanoacetic acid anions at pH 9.24. For the catalyzed reaction, the Hammett reaction constant p = 2.72. For the uncatalyzed reaction, p = 2.44. Fig. 8. Hammett pa correlations for the cycloheptaamylose-catalyzed ( ) and the uncatalyzed (O) decarboxylation of phenylcyanoacetic acid anions at pH 9.24. For the catalyzed reaction, the Hammett reaction constant p = 2.72. For the uncatalyzed reaction, p = 2.44.
Ethylenimine, 30, 38 toxic properties of, 30, 40 Ethyl o-ethoxybenzoate, 32, 75 Ethyl formate, 32, 32 Ethyl glycidyl ether, 31, 3 2-Ethylhexanaldoxime, 32, 67 2-Ethylhexanamide, 32, 65 2-Ethylhexanoic acid, 32, 66 2-Ethylhexanonitrile, 32, 65 Ethylidene bromide, 32, 55 Ethyl iodide, 31, 34 Ethyl isodehydroacetate, 32, 76 Ethyl lactate, 31, 59, 60 5-ETHYL-2-METHYLPYRIDINE, 30, 41 Ethyl orthocarbonate, 32, 68 Ethyl orthoformate, 32, 5 Ethyl orthosilicate, 32, 5 Ethyl phenylazoacetoacetate, 32, 85 Ethyl phenylcyanoacetate, 30,43,80 Ethyl 0-phenyl-/3-cyanopropionate, 30, 84... [Pg.55]

Creosol, 33, 17 Crotonaldehyde, 33, IS 34, 29 diethyl acetal, 32, 5 Cupric acetate monohydrate, 36, 77 Cuprous oxide-silver oxide, 36, 36, 37 Cyanamide, 34, 67 36, 8 Cyanoacetamide, 32, 34 Cyanoacetic acid, 31, 25 Cyanoacetylurea, 37, 16 >-Cyanobenzaldehyde, 30, 100 >-Cyanobenzaldiacetate, 36, 59 3-Cyano-5,6-dimethyl-2(l)-pyridone, 32,34 N-2-Cyanoethylaniline, 36, 6 N-2-Cyanoethyl- -anisidine, 36, 7 Cyanoethylation, of aniline, 36, 6 of ethyl phenylcyanoacetate, 30, 80 N-2-Cyanoethyl-m-chloroaniline, 36, 7 Cyanogen, 32, 31 Cyanogen iodide, 32, 29 Cyanogen iodide, complex with sodium iodide, 32, 31... [Pg.47]

The acidity constants of protonated ketones, pA %, are needed to determine the free energy of reaction associated with the rate constants ArG° = 2.3RT(pKe + pK ). Most ketones are very weak bases, pAT < 0, so that the acidity constant K b cannot be determined from the pi I rate profile in the range 1 < PH <13 (see Equation (11) and Fig. 3). The acidity constants of a few simple ketones were determined in highly concentrated acid solutions.19 Also, carbon protonation of the enols of carboxylates listed in Table 1 (entries cyclopentadienyl 1-carboxylate to phenylcyanoacetate) give the neutral carboxylic acids, the carbon acidities of which are known and are listed in the column headed pA . As can be seen from Fig. 10, the observed rate constants k, k for carbon protonation of these enols (8 data points marked by the symbol in Fig. 10) accurately follow the overall relationship that is defined mostly by the data points for k, and k f. We can thus reverse the process by assuming that the Marcus relationship determined above holds for the protonation of enols and use the experimental rate constants to estimate the acidity constants A e of ketones via the fitted Marcus relation, Equation (19). This procedure indicates, for example, that protonated 2,4-cyclohexadienone is less acidic than simple oxygen-protonated ketones, pA = —1.3. [Pg.352]

ETHYL PHENYLCYANOACETATE (Acetic acid, cyanophenyl-, ethyl ester)... [Pg.43]


See other pages where Phenylcyanoacetic acid is mentioned: [Pg.243]    [Pg.362]    [Pg.362]    [Pg.243]    [Pg.362]    [Pg.362]   
See also in sourсe #XX -- [ Pg.117 , Pg.362 ]

See also in sourсe #XX -- [ Pg.117 , Pg.362 ]




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