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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Conrotatory ring-opening reactions of cyclopropyl anions in monocyclic and tricyclic systems
Olalla Nieto Faza1, Carlos Silva López, Rosana Alvarez
1Departamento de Química Orgánica, Facultad de Química, Universidad de Vigo, Lagoas-Marcosende s/n, 36200 Vigo, Spain.
Abstract:
[reaction: see text] Only conrotatory transition structures were located by B3LYP6-311++G(3df, 2p) computations for the electrocyclic ring opening of cyclopropyl anions having different substituents (H, Me, CN). The transition structure for the similarly substituted cyclopropyl anion fused to a bicyclic system exhibits the same features, in apparent contradiction with the observed product. A reaction path where the direction of twist changes after the transition state provides an explanation alternative to those proposed in recent reports.
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