Foiled carbene

s.

The increased stabilization blocks certain otherwise ordinary reaction modes for the carbene hence the term "foiled". An example is "norbornen-7-ylidene" which is norbornene with a carbenic carbon atom at the bridge position. In silico experiments reveal that the bridge in this molecule is actually bending towards the double bond with an optimum angle of around 90° vs 130° for norbornene ["The Nature and Extent of -Stabilization within Foiled Carbenes" Jean-Luc Mieusset and Udo H. Brinker J. Am. Chem. Soc.; 2006; 128(49) pp 15843 - 15850; (Article) DOI|10.1021/ja065595y] ["Foiled Carbenes Revisited: When -Stabilization Surpasses -Stabilization" Jean-Luc Mieusset and Udo H. Brinker J. Org. Chem.; 2007; 72(1) pp 263 - 268; (Article) DOI|10.1021/jo062074k] .

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