Differential electrolytic potentiometry with periodic polarisation. Part XXVII. Direct and mark-space biased periodic polarisation in substitution, addition and oxidation titrimetry with dibromine in anhydrous acetic acid

The Analyst ◽  
1983 ◽  
Vol 108 (1291) ◽  
pp. 1227 ◽  
Author(s):  
Adballa M. S. Abdennabi ◽  
E. Bishop
Keyword(s):  
Acetic Acid ◽  
Anhydrous Acetic Acid ◽  
Electrolytic Potentiometry

scholarly journals Abraham model correlations for estimating solute transfer of neutral molecules into anhydrous acetic acid from water and from the gas phase

2015 ◽  
Vol 212 ◽  
pp. 16-22 ◽  
Author(s):  
Dawn M. Stovall ◽  
Amber Schmidt ◽  
Colleen Dai ◽  
Shoshana Zhang ◽  
William E. Acree ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Gas Phase ◽  
Solute Transfer ◽  
Abraham Model ◽  
Anhydrous Acetic Acid

Anodic oxidation of halides in anhydrous acetic acid

1973 ◽  
Vol 44 (1) ◽  
pp. 37-45 ◽  
Author(s):  
M. Mastragostino ◽  
G. Casalbore ◽  
S. Valcher
Keyword(s):  
Acetic Acid ◽  
Anodic Oxidation ◽  
Anhydrous Acetic Acid

N-Methylamino Acids in Peptide Synthesis. III. Racemization during Deprotection by Saponification and Acidolysis

1973 ◽  
Vol 51 (15) ◽  
pp. 2555-2561 ◽  
Author(s):  
John R. McDermott ◽  
N. Leo Benoiton
Keyword(s):  
Acetic Acid ◽  
Sodium Hydroxide ◽  
Hydrogen Bromide ◽  
Aqueous Sodium Hydroxide ◽  
Acid Strength ◽  
Carboxyl Group ◽  
Aqueous Sodium ◽  
Aqueous Acid ◽  
Amino Acid Analyzer ◽  
Anhydrous Acetic Acid

The racemization of N-methylamino-acid derivatives in aqueous sodium hydroxide and hydrogen bromide in anhydrous acetic acid and other solvents has been investigated by determining the products of the reaction with an amino-acid analyzer after deprotection. Whereas MeIle-OMe, Z-MeIle, and the N-unmethylated derivatives were only slightly racemized ( <2%), Z-MeIle-OMe (18–24%), Z-Ala-MeLeu-OMe (22%), and Z-Ala-MeLeu-OBu′ (7%) were appreciably racemized by aqueous sodium hydroxide. It is suggested that these derivatives racemize because of the absence of an > N—H or carboxyl group whose ionization would suppress ionization of the neighboring α-C—H bond. Z-Melle and Z-Ala-MeLeu were substantially racemized (68% in 4 h and 34% in 1 h, respectively) by 5.6 N hydrogen bromide in acetic acid. The extent of racemization by acid varied with acid strength, polarity of solvent, and time. Incorporation of label into both isomers of Ala-MeLeu from a solution of the tritiated reagent established that ionization at the α-C—H bond had occurred. No racemization was caused by aqueous acid or by hydrogen chloride.

Screened indicators in anhydrous acetic acid medium: Chromatic evaluation of their transitions

1991 ◽  
Vol 105 (1-3) ◽  
pp. 89-99 ◽  
Author(s):  
Jos� Barbosa ◽  
Elisabeth Bosch ◽  
Jos� Luis Cortina ◽  
Mart� Ros�s
Keyword(s):  
Acetic Acid ◽  
Acid Medium ◽  
Acetic Acid Medium ◽  
Screened Indicators ◽  
Anhydrous Acetic Acid
Sign in / Sign up

Export Citation Format

Share Document