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A tris-spiro metalla-aromatic system featuring Craig-Mobius aromaticity.

ABSTRACT: As aromaticity is one of the most fundamental concepts in chemistry, the construction of aromatic systems has long been an important subject. Herein, we report the synthesis and characterization of a tris-spiroaromatic complex, hexalithio spiro vanadacycle 2. The delocalization of the four electrons within the two V 3d orbitals and the ?* orbitals of the three biphenyl ligands leads to a 40? Craig-Möbius aromatic system with three metalla-aromatic rings, as revealed by both experimental measurements and theoretical analyses. For comparison, if Cr is used instead of V, a similar Craig-Möbius aromatic system can not be generated. In this case, pentalithio spiro chromacycle 3 is obtained, and the Cr center uses its two 3d orbitals to form two independent metalla-aromatic rings. This work presents a type of aromatic systems that will contribute to both aromaticity theory and organometallic chemistry.

SUBMITTER: Huang Z

PROVIDER: S-EPMC7910433 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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A tris-spiro metalla-aromatic system featuring Craig-Möbius aromaticity.

Huang Zhe Z Zhang Yongliang Y Zhang Wen-Xiong WX Wei Junnian J Ye Shengfa S Xi Zhenfeng Z

Nature communications 20210226 1

As aromaticity is one of the most fundamental concepts in chemistry, the construction of aromatic systems has long been an important subject. Herein, we report the synthesis and characterization of a tris-spiroaromatic complex, hexalithio spiro vanadacycle 2. The delocalization of the four electrons within the two V 3d orbitals and the π* orbitals of the three biphenyl ligands leads to a 40π Craig-Möbius aromatic system with three metalla-aromatic rings, as revealed by both experimental measurem ...[more]

PMID: 33637738

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