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Synthesis, structure and aromaticity of carborane-fused carbo- and heterocycles.

ABSTRACT: Conjugation between a 3-D icosahedral carborane and a fused 2-D ?-ring system is ambiguous. To address this issue, we prepared several carborane-fused carbo- and heterocycles. Detailed studies on their molecular structures, NMR data, and NICS (nucleus-independent chemical shift) and ISE (isomerization stabilization energy) values as well as molecular orbital analyses clearly suggest the presence of (1) considerable aromatic character in the exo five-membered ring of carborane-fused carbo- and heterocycles and (2) considerable conjugation between a 3-D carborane and a fused 2-D ?-ring system. These results will shed some light on the design of new carborane-based materials.

SUBMITTER: Chan TL

PROVIDER: S-EPMC5897843 | biostudies-other | 2018 Feb

REPOSITORIES: biostudies-other

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Synthesis, structure and aromaticity of carborane-fused carbo- and heterocycles.

Chan Tek Long TL Xie Zuowei Z

Chemical science 20180116 8

Conjugation between a 3-D icosahedral carborane and a fused 2-D π-ring system is ambiguous. To address this issue, we prepared several carborane-fused carbo- and heterocycles. Detailed studies on their molecular structures, NMR data, and NICS (nucleus-independent chemical shift) and ISE (isomerization stabilization energy) values as well as molecular orbital analyses clearly suggest the presence of (1) considerable aromatic character in the <i>exo</i> five-membered ring of carborane-fused carbo- ...[more]

PMID: 29719701

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