Premium
Dynamic effects in the didehydro‐Diels‐Alder ( DDDA ) reaction of enyne‐ketoenes: 50% stepwise bond formation in spite of concerted transition state
Author(s) -
Rana Anup,
Paul Indrajit,
Schmittel Michael
Publication year - 2017
Publication title -
journal of physical organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.325
H-Index - 66
eISSN - 1099-1395
pISSN - 0894-3230
DOI - 10.1002/poc.3732
Subject(s) - diradical , enyne , chemistry , concerted reaction , computational chemistry , transition state , reaction mechanism , reaction intermediate , chemical physics , catalysis , organic chemistry , physics , atomic physics , singlet state , excited state
The C 2 ─C 6 /Diels‐Alder cyclization of enyne‐ketoene 1 was studied by experiments, theoretical calculations, and dynamic trajectory computations. The failure to trap possible intermediate(s), indicates a concerted reaction mechanism. A detailed search for stationary points revealed a concerted mechanism and surprisingly a diradical intermediate with no direct connection to the enyne‐ketoene 1 . To probe the accessibility of this intermediate quasiclassical trajectories were initiated from the concerted transition state structure. Notably, 36% of the trajectories reach the product zone directly and 5% arrive at the product via the intermediate diradical. Additionally, 31% of the trajectories go to the intermediate zone and stay there within the simulation time limit.