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Theoretical studies of the gas‐phase pyrolysis kinetics of ω‐bromonitriles, ZCH 2 CH 2 Br [Z = NC, NCCH 2 , NCCH 2 CH 2 ]
Author(s) -
Rojas Jose R.,
Loroño Marcos,
Mora Jose R.,
Dominguez Rosa M.,
Cordova Tania,
Chuchani Gabriel
Publication year - 2009
Publication title -
international journal of chemical kinetics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.341
H-Index - 68
eISSN - 1097-4601
pISSN - 0538-8066
DOI - 10.1002/kin.20392
Subject(s) - chemistry , gas phase , substituent , yield (engineering) , kinetic energy , kinetics , thermodynamics , stereochemistry , physics , quantum mechanics
The gas‐phase elimination of several ω‐bromonitriles (ZCH 2 CH 2 Br, Z = NC, NCCH 2 , NCCH 2 CH 2 ) has been examined at the MP2/6‐31G(d,p), MP2/6‐31G(2d,2p), B3PW91/6‐31G(2d,2p), and MPW91PW91/6‐31(2p,2d) levels of theory. The bromonitriles yield the corresponding cyano‐olefin and HBr gas in a rate‐determining step. The MPW91PW91/6‐31G(2p,2d) results suggest a concerted mechanism, with a polar, four‐membered transition state. The calculated kinetic and thermodynamic parameters were found to be within reasonable agreement with the experimental determinations. Substituent effects are discussed in terms of electronic structure. © 2008 Wiley Periodicals, Inc. Int J Chem Kinet 41: 168–175, 2009