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Abstract Whether tetra‐tert‐butyl‐s‐indacene is a symmetricD2hstructure or a bond‐alternatingC2hstructure remains a standing puzzle. Close agreement between experimental and computed proton chemical shifts based on minima structures optimized at the M06‐2X, ωB97X‐D, and M11 levels confirm a bond‐localizedC2hsymmetry, which is consistent with the expected strong antiaromaticity of TtB‐s‐indacene.
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Computational comparison of paratropicity trends in antiaromatic s ‐indacene derivatives: Does the functional “make all the difference”?
Abstract A recent publication by Wu and co‐workers demonstrated that the workhorse functional B3LYP tends to overemphasize the delocalization in antiaromatic molecules, leading to poor agreement between the calculated proton NMR values and the experimentally obtained numbers. Rather, they showed that the M11 functional affords the best agreement between theory and experiment. We have computationally re‐examined our previously published NICS‐XY scan data using M11‐determined geometries and find that, aside from the placement ofs‐indacene, the antiaromaticity trends for both sets of data are essentially identical.
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- Award ID(s):
- 2246964
- PAR ID:
- 10523969
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Physical Organic Chemistry
- Volume:
- 38
- Issue:
- 2
- ISSN:
- 0894-3230
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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