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Coupling molecules to a quantized radiation field inside an optical cavity has shown great promise in modifying chemical reactivity. It was recently proposed that strong light-matter interactions are able to differentiate endo/exo products of a Diels-Alder reaction at the transition state. Using the recently developed parameterized quantum electrodynamic \textit{ab initio} polariton chemistry approach along with time-dependent density functional theory, we theoretically confirm that the ground state selectivity of a Diels-Alder reaction can be fundamentally changed by strongly coupling to the cavity, generating preferential endo or exo isomers which are formed with equal probability for the same reaction outside the cavity. This provides an important and necessary benchmark with the high-level self-consistent QED coupled cluster approach. In addition, by computing the ground state difference density, we show that the cavity induces a redistribution of electron density from intramolecular $$\pi$$-bonding orbitals to intermolecular bonding orbitals, thus providing chemically relavent description of the cavity-induced changes to the ground state chemistry and thus changes to the molecular orbital theory inside the cavity. We extend this exploration to an arbitrary cavity polarization vector which leads to critical polarization angles that maximize the endo=/exo selectivity of the reaction. Finally, we decompose the energy contributions from the Hamiltonian and provide discussion relating to the dominent dipole self-energy effects on the ground state.
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This content will become publicly available on June 1, 2026
Crystal structure, computational study, and Hirshfeld analysis of exo -1,2,3,5-tetraphenyl-1a',9b'-dihydrospiro[bicyclo[3.1.0]hexane-6,1′-cyclopropa[ l ]phenanthren]-2-en-4-one
The reaction of dibenzonorcarynyliden(e/oid) with phencyclone was recently reported to give a congested spiropentane withendostereochemistry. Herein we report that, in sharp contrast, an analogous reaction using tetracyclone, instead of phencyclone, gives the highly crowded title spiropentane but withexostereochemistry as determined by X-ray crystallography. This new tetracyclone adduct (C44H30O) crystallizes upon slow evaporation from hexanes/ethyl acetate in the monoclinic crystal system andP21/n(No. 14) space group. It has one molecule in the asymmetric unit and four molecules per unit cell. DLPNO-CCSD(T)/def2-TZVP//B3LYP/def2-SVP calculations indicate that theendospiropentane diastereomers from phencyclone and tetracyclone are both more stable than the correspondingexoforms by 6.68 and 5.35 kcal mol−1, respectively. As noted previously in the phencyclone system, favorable π-stacking interactions between the two flat biphenyl moieties in the product and transition state may lead to the preferential formation of theendodiastereomer. However, the ability of the phenyl rings in the 3,4-position of the tetracyclone component to rotate could introduce destabilizing steric interactions in the transition state that hinder formation of theendodiastereomer in favor of the less thermodynamically stableexoisomer.
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- Award ID(s):
- 2400007
- PAR ID:
- 10614505
- Publisher / Repository:
- IUCr
- Date Published:
- Journal Name:
- Acta Crystallographica Section E Crystallographic Communications
- Volume:
- 81
- Issue:
- 6
- ISSN:
- 2056-9890
- Page Range / eLocation ID:
- 554 to 558
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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