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Sequential Tether-Directed Synthesis of New [3 : 2 : 1] Hexakis-Adducts of C₆₀ with a Mixed Octahedral Addition Pattern.

ABSTRACT: A new concept for the regioselective synthesis of [3 : 2 : 1] hexakis-adducts of fullerene C₆₀ was developed. Based on sequential tether-directed remote functionalizations, chiral [3 : 2] pentakis-adducts with an incomplete octahedral addition pattern were synthesized via stepwise cyclopropanation of C₆₀ with suitable macrocyclic tri- and bifunctional cyclomalonate tethers. The four resulting stereoisomers were isolated using chiral HPLC. The corresponding pairs of enantiomers show mirror image behavior in their CD-spectra. The pentakis-adducts served as suitable building blocks for the spatially controlled synthesis of mixed hexakis-adducts. Implementation of functional group-bearing monomalonates afforded octahedral [3 : 2 : 1] hexakis-adducts suitable for the construction of larger molecular and supramolecular fullerene architectures in excellent yield.

SUBMITTER: Wachter M

PROVIDER: S-EPMC8251792 | biostudies-literature | 2021 May

REPOSITORIES: biostudies-literature

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Sequential Tether-Directed Synthesis of New [3 : 2 : 1] Hexakis-Adducts of C60 with a Mixed Octahedral Addition Pattern.

Wachter Michael M Jurkiewicz Lisa L Hirsch Andreas A

Chemistry (Weinheim an der Bergstrasse, Germany) 20210502 28

A new concept for the regioselective synthesis of [3 : 2 : 1] hexakis-adducts of fullerene C60 was developed. Based on sequential tether-directed remote functionalizations, chiral [3 : 2] pentakis-adducts with an incomplete octahedral addition pattern were synthesized via stepwise cyclopropanation of C60 with suitable macrocyclic tri- and bifunctional cyclomalonate tethers. The four resulting stereoisomers were isolated using chiral HPLC. The corresponding pairs of enantiom ...[more]

PMID: 33792116

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