C-13 isotope effects in the decarboxylation of phenylpropiolic acid (PPA) in water solution of formic acid (FA)

• Autorzy: Zieliński M. , Zielińska A. , Ogrinc N. , Kobal I. , Paul H. , Bernasconi S. , Papiernik-Zielińska H.
• Języki publikacji: EN

Abstrakty

EN

Kinetics and the carbon-13 kinetic isotope effects in the decarboxylation of phenylpropiolic acid in HCOOH/H2O, 1:1/V:V, solution have been examined between 80-140.13oC. 13C KIE in the decarbonylation of formic acid, proceeding with measurable rate in this medium between 130-150oC, has determined also and compared with corresponding values found in the pure HCOOH/H2O solution. Kinetics and C-13 KIE in the decarboxylation of phenylpropiolic acid in pure water have been investigated subsequently between 100-143oC in all glass reaction vessels sealed under vacuum. The enthalpy of activation of decarboxylation of PPA in pure water, 30.20 kcal/mol, and the entropy of activation, DS* = -3.7 e.u., are by 6.7 kcal/mol and 12.5 e.u., respectively, higher than the DH* and DS* values found in the decarboxylation of PPA in pure formic acid. The C-13 KIE equal to 1.004-1.005 between 70-100oC in the pure HCOOH medium increased to C-13 KIE of 1.020 in the case of decarboxylation of PPA at 133.7oC in the initially pure water.

Słowa kluczowe

EN

phenylopropiolic acid; formic acid; water/formic acid solutions; decarboxylations; decarbonylations; activation parameters; carbon-13 isotope effects

• Wydawca: Polskie Towarzystwo Chemiczne
• Czasopismo: Polish Journal of Chemistry
• Rocznik: 1999
• Tom: vol. 73 nr 5
• Strony: 813--820

Twórcy

autor

Zieliński M.

autor

Zielińska A.

autor

Ogrinc N.

autor

Kobal I.

autor

Paul H.

autor

Bernasconi S.

autor

Papiernik-Zielińska H.

• Wydział Chemii Uniwersytet Jagielloński 30-060 Kraków