An unexpected Ireland–Claisen rearrangement cascade during the synthesis of the tricyclic core of Curcusone C: Mechanistic elucidation by trial-and-error and automatic artificial force-induced reaction (AFIR) computations
| Autor: | Buck L. H. Taylor, Keiji Morokuma, Ashay Patel, Brian M. Stoltz, K. N. Houk, Chung Whan Lee, Galina P. Petrova |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Pericyclic reaction
Silylation Stereochemistry Chemistry Total synthesis General Chemistry 010402 general chemistry 01 natural sciences Biochemistry Catalysis 0104 chemical sciences Claisen rearrangement Colloid and Surface Chemistry Isomerism Models Chemical Cascade Mechanism (philosophy) Diterpenes Algorithms Density Functional Theory Ireland–Claisen rearrangement Cope rearrangement |
| Popis: | In the course of a total synthesis effort directed toward the natural product curcusone C, the Stoltz group discovered an unexpected thermal rearrangement of a divinylcyclopropane to the product of a formal Cope/1,3-sigmatropic shift sequence. Since the involvement of a thermally forbidden 1,3-shift seemed unlikely, theoretical studies involving two approaches, the “trial-and-error” testing of various conceivable mechanisms (Houk group) and an “automatic” approach using the Maeda–Morokuma AFIR method (Morokuma group) were applied to explore the mechanism. Eventually, both approaches converged on a cascade mechanism shown to have some partial literature precedent: Cope rearrangement/1,5-sigmatropic silyl shift/Claisen rearrangement/retro-Claisen rearrangement/1,5-sigmatropic silyl shift, comprising a quintet of five sequential thermally allowed pericyclic rearrangements. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|