AB-INITIO STUDY ON THE 1 2-REACTION OF CO2 WITH DIMETHYLAMINE/

The reaction between CO2 and the dimethylamine molecule in the presenc e of a second dimethylamine molecule is modeled by the ab initio RHF/3 -21G method. Starting from the most stable 1:2 complex, the most effec tive reaction pathway turned out to be proton transfer between amine m olecules followed by immediate proton transfer from one of the amine m olecules to the CO2 moiety. The activation barrier for this pathway (9 .54 kcal mol(-1) with respect to the 1:2 complex) is within the range of activation energy values found in kinetic studies for similar react ions with different hydroxylamines (from 9.2 to 13.0 kcal mol(-1)). Th e reaction product is the cyclic hydrogen bonded complex of dimethylca rbamic acid with dimethylamine. (C) 1997 Elsevier Science B.V.