Accession Number : AD0676423

Title :   REACTIONS OF TRIFLUOROACETIC ACID WITH POLY (VINYL ALCOHOL) AND ITS MODEL COMPOUNDS. EFFECT OF NEIGHBORING HYDROXYL GROUPS ON THE REACTION,

Corporate Author : NATIONAL RESEARCH COUNCIL OF CANADA OTTAWA (ONTARIO) DIV OF APPLIED CHEMISTRY

Personal Author(s) : Fujii,K. ; Brownstein,S. ; Eastham,A. M.

Report Date : 21 DEC 1967

Pagination or Media Count : 10

Abstract : Reactions of trifluoroacetic acid with poly(vinyl alcohol) and various model alcohols were investigated by observing the fluorine and the proton magnetic resonance spectra of the reaction mixtures. At equilibrium the degree of conversion to ester under given conditions decreased in the order isopropanol, pentane-2,4-diol, heptane-2,4,6-triol and poly(vinyl alcohol). Therefore the equilibrium constant for esterification of a hydroxyl group is depressed by the presence of neighboring hydroxyl groups. It was observed that the steric structures of the models and polymers also affect the equilibrium position of the reaction and this is mainly ascribable to the fact that meso (isotactic) molecules react more slowly with the acid than do racemic (syndiotactic) molecules. In acid-catalyzed acetylation of the model alcohols with acetic acid no similar dependence on the steric configuration was found. Therefore trifluoroacetylation seems to be specific in this respect. (Author)

Descriptors :   (*POLYVINYL ALCOHOL, CHEMICAL REACTIONS), (*ALCOHOLS, ACETYLATION), HALOGENATED HYDROCARBONS, FLUORINE COMPOUNDS, ACETIC ACID, ESTERS, SYNTHESIS(CHEMISTRY), NUCLEAR MAGNETIC RESONANCE, STEREOCHEMISTRY, PROPANOLS, GLYCOLS, CANADA

Subject Categories : Organic Chemistry
      Plastics

Distribution Statement : APPROVED FOR PUBLIC RELEASE