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Kinetic and Mechanistic Insights into the Pathway Leading to Cyclic Crystalline Phosphorus Ylide Formation in the Presence of 3‐Chloropentane‐2,4‐dione: Theoretical and Stopped‐Flow Approaches
Author(s) -
HabibiKhorassani Sayyed Mostafa,
Ebrahimi Ali,
Maghsoodlou Malektaher,
Asheri Osman,
Shahraki Mehdi,
Akbarzadeh Niloufar,
Ghalandarzehi Younes
Publication year - 2013
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.20797
Subject(s) - chemistry , kinetic energy , ylide , reaction mechanism , triphenylphosphine , ring (chemistry) , computational chemistry , reaction rate , kinetics , photochemistry , stereochemistry , catalysis , organic chemistry , physics , quantum mechanics
In this work, three speculative mechanisms of the reaction between triphenylphosphine and dimethyl acetylendicarboxylate in the presence of 3‐chloropentane‐2,4‐dione were energetically and thermodynamically developed using quantum mechanical calculations and were profoundly compared with stopped‐flow and UV spectrophotometry approaches. The third speculative mechanism that led to the five‐membered ring structure was experimentally and theoretically favorable. The five‐membered ring structure of product was characterized by X‐ray crystallographic data. Also, steps 1 and 2 of the third mechanism were determined as fast and rate‐determining steps, respectively. The experimental kinetic evidence of the formation and decay of intermediate in steps 1 and 2 (fast and rate‐determining steps, respectively) was compatible with theoretical data. Experimental kinetic data were recognized for overall reaction along with activation parameters for fast and rate‐determining steps of the reaction. Theoretical kinetic data ( k and E a ) and activation parameters (Δ G ≠ , Δ S , ≠ and Δ H ≠ ) were calculated for each step and overall reactions.