Control of Aromaticity and cis‐/trans‐Isomeric Structure of Non‐Planar Hexaphyrin(2.1.2.1.2.1) and Metal Complexes

• Published in: Angewandte Chemie International Edition Vol. 58; no. 36; pp. 12524 - 12528
• Main Authors: Xue, Songlin, Kuzuhara, Daiki, Aratani, Naoki, Yamada, Hiroko
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 02.09.2019; Wiley Subscription Services, Inc
• Edition: International ed. in English
• Subjects: Aromaticity; aromaticity conversion; Chemical reactions; Chemistry; Chemistry, Multidisciplinary; Coordination compounds; Copper compounds; distorted porphyrins; Distortion; isomerization; Metal complexes; Metal ions; Physical Sciences; porphyrinoids; Science & Technology; Zinc; metal complexes; porphyrinoids; MOBIUS AROMATICITY; isomerization; TRANS-ISOMERIZATION; EXPANDED PORPHYRINS; aromaticity conversion; distorted porphyrins; MOLECULES
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.201906946

Vinylene‐bridged hexaphyrin(2.1.2.1.2.1) was synthesized from dipyrrolyl diphenylethenes by acid‐catalyzed condensation reactions. Freebase hexaphyrin(2.1.2.1.2.1) forms a distorted structure with non‐aromatic characteristics. The aromaticity and molecular configuration of non‐planar hexaphyrin(2.1.2.1.2.1) can be controlled by insertion of metal ions. Freebase and zinc complexes show a distorted structure without macrocyclic aromaticity, whereas copper complexes show a figure‐of‐eight structure with macrocyclic aromaticity. It is the first example of aromaticity conversion of a distorted expanded porphyrin involving vinylene bridges. A vinylene‐bridged hexaphyrin (Hex) was synthesized. The aromaticity and molecular configuration of non‐planar Hex can be controlled through the insertion of zinc and copper ions. The zinc complex forms a distorted non‐aromatic structure, whereas copper complexes show a figure‐of‐eight structure with macrocyclic aromaticity. This is the first example of aromaticity conversion of distorted expanded porphyrins involving vinylene bridges.