A simple and modular route to arylcycloheptene scaffolds is reported. The two-step route from Knoevenagel adducts and allylic electrophiles is made possible through the design of a Cope rearrangement that utilizes a "traceless" activating group to promote an otherwise thermodynamically unfavorable transformation. Experimentally, the [3,3] rearrangement occurrs transiently at room temperature with a computed barrier of 19.5 kcal mol, which ultimately allows for three-component bis-allylation. Ring-closing metathesis delivers the arylcycloheptane and removes the activating group. This report describes the design and optimization of the methodology, scope and mechanistic studies, and computational analysis.
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| http://dx.doi.org/10.1039/c8sc03057j | DOI Listing |
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Article Synopsis
- The text discusses advancements in transition-metal catalyzed asymmetric allylic substitution, particularly focusing on the challenges of directly arylating acyclic internal alkenes.
- It introduces a new method called interrupted asymmetric allylic substitution-isomerization (Int-AASI), which allows for the successful asymmetric allylic arylation of these compounds.
- The research demonstrates high enantioselectivity in producing allylic arylation products and axial chiral alkenes, supported by experimental findings and density functional theory studies to explain the observed selectivities.
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