Kinetic isotope effect for hydrogen/deuterium abstraction by chlorine atoms from (CH3)2NNO2 and (CD3)2NNO2

✍ Scribed by Yannis G. Lazarou; Panos Papagiannakopoulos

• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 462 KB
• Volume: 25
• Category: Article
• ISSN: 0538-8066
• DOI: 10.1002/kin.550250403

✦ Synopsis

The kinetic isotope effect for the abstraction of hydrogenideuterium from dimethylnitramine and dimethylnitramine-ds by chlorine atoms has been studied in the temperature range 273-353 K. The rate constant ratio k H / k D is given by the Arrhenius expression, k H / k o = (0.92 t-0.07)exp(286 ? 250/RT), where R is expressed in cal mol-' K-'. The absolute rate constant for the deuterium abstraction reaction is extrapolated as k D = (1.50 t-0.90) X exp(-1,486 i 370/RT) cm3 molecule-' s-l. The temperature dependence of the kinetic isotope effect was calculated using the conventional transition-state theory, and the obtained values for AH/AD and A E H , ~ are in good agreement with the experimental value for a bent transition state geometry, with two new vibrational frequencies of 340 cm-' (272 cm-') corresponding to the in-plane and out-of-plane motions of hydrogen (deuterium) atoms in the C1 . . .