Convergent, Regioselective Synthesis of Tetrakisfulleroids from C60

• Published in: Journal of organic chemistry Vol. 67; no. 22; pp. 7683 - 7687
• Main Authors: Qian, Wenyuan, Rubin, Yves
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 01.11.2002
• Subjects: Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Fullerenes and related materials; diamonds, graphite; Materials science; Physics; Specific materials; Intramolecular reaction; Chemical rearrangement; Acetylenic compound; Regioselectivity; Esters; Tandem reaction; Diels Alder adduct; Ring cleavage; Aromatics; Cyclobutane derivatives; Trans stereoisomer; Fullerenes; Cleavage; Ring contraction; Carbon molecules; Chemical synthesis; Ethylenic compound; Diastereomer; Atomic clusters; Photochemistry; Ultraviolet visible spectrometry
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo026033+

An efficient synthesis of the two diastereomeric tetrakisfulleroids 14a and 14b is described starting from the readily accessible trans-1 bis-Diels−Alder adduct 12. The challenging issue of generating multiple bond scissions regiochemically within the fullerene framework, here as [5,6] open systems (fulleroids), is simplified into performing two separate regiocontrol phases. The initial bisadduct 12 can only undergo syn or anti photochemically promoted intramolecular tandem [4 + 4] and retro [2 + 2 + 2] rearrangements, giving the two isomers 14a and 14b in an unexpected 1:4 ratio. Interestingly, the UV−vis absorption spectra of these two isomers are quite different even though their local chromophore perturbations are distant from each other.