Kinetics Database Resources
Rate Our Products and Services
Other Databases
NIST Standard Reference Data Program
NDRL-NIST Solution Kinetics Database
NIST Computational Chemistry Comparison and Benchmark Database
The NIST Reference on Constants, Units, and Uncertainty
Administrative Links
 |
Home ©NIST, 2013 Accessibility information |
Title: Mechanism of elimination of amino acid derivatives in the gas phase. Pyrolysis kinetics of ethyl picolinate, ethyl 1-methylpipecolinate and picolinic acid
Journal: J. Phys. Org. Chem.
Volume: 16
Page(s): 84 - 88
Year: 2003
Reference type: Journal article
Squib: 2003LAF/ENS84-88
Reaction:
2-Pyridinecarboxylic acid ethyl ester → C2H4 + Pyridine + CO2
Reaction order:
1
Temperature:
623 - 687
K
Rate expression:
2.0x1011 [±1.0x1011 s-1] e-180900 [±3000 J/mole]/RT
Category: Experiment
Data type:
Absolute value measured directly
Pressure dependence:
None reported
Experimental procedure:
Static or low flow - Data taken vs time
Excitation technique:
Thermal
Time resolution:
In real time
Analytical technique:
Pressure measurement
Comments:
The authors suggest decomposition proceeds via a two step mechanism with an initial molecular elimination reaction to give ethene and 2-pyridinecarboxylic acid (picolinic acid) followed by rapid decomposition of the latter compound to pyridine and CO2. The reported kinetic results on picolinic acid decomposition support this interpretation.
Kinetics were determined by following pressure vs. time with additional support via quantitative analysis of ethen via gas chromatography.
Uncertainties are precision only and are at the 90% confidence level.
View full bibliographic record.
Rate constant values calculated from the Arrhenius expression:
| T (K) | k(T) [s-1] |
|---|---|
| 623 | 1.35E-4 |
| 625 | 1.52E-4 |
| 650 | 5.81E-4 |
| 675 | 2.01E-3 |
| 687 | 3.56E-3 |