Towards the Rational Synthesis of Norfullerenes. Controlled Deletion of One Carbon Atom from C₆₀ and Preparation of 2,5,9-Trioxo-1-nor(C₆₀-I_h)[5,6]fullerene C₅₉(O)₃ Derivatives

Abstract

Norfullerenes are fullerene-like compounds (fulleroids) resulting from partial deletion of fullerene skeleton carbons. The one carbon less norfullerene C59(O) 3 derivatives having three carbonyl groups on the rim of the orifice are prepared through peroxide-mediated reactions. A key step involves a novel PCl 5 initiated rearrangement of a hydroxyl amine adduct. Decarboxylation serves as the carbon removal step.

Peroxide‐Mediated Selective Cleavage of [60]Fullerene Skeleton Bonds: Towards the Synthesis of Open‐Cage Fulleroid C55O5

“…The initial step is reminiscent of a Beckmann‐type rearrangement. A rather similar hydroxylamine rearrangement process was observed by treating the analogous compound 27 with PCl 5 . This process eventually led to the preparation of the triketone C 59 product 28 .…”

Water‐Mediated Thermal Rearrangement of a Cage‐Opened C60 Derivative

“…These reactions are mainly driven by the strain release from the C 60 cage. During the course of studies on the Stieglitz rearrangement, [12] they succeeded in synthesizing the first tricarbonyl norfullerene (C 59 O 3 R 2 ) from a hydroxylamine derivative of fullerene-mixed peroxides via a PCl 5 -initiated rearrangement in which one of carbon atoms was moved out of the fullerene skeleton with a migration of a t-butoxy group onto the N-atom. As another example, the phospha-Brook rearrangement enables the introduction of a phosphoryl group which works as a stopper to prevent the encapsulated molecule from escaping.…”

Punching a Carbon Atom of C60 into its Own Cavity to Form an Endohedral Complex CO@C59O6 under Mild Conditions

“…The formation of open-cage fullerene derivatives involved deletion of one skeleton carbon atom in a few cases. [12][13][14][15][16][17] In all these examples, the cleaved fullerene carbon atom(s) was eliminated from the cage rather than trapped inside the cavity.…”

“…Fullerene-bound hydroxylamino group is prone to rearrangement as shown in our previous studies. [11,14,21] To expand the orifice we treated compound 4 with diacetoxyl iodobenzene (DIB). To our surprise, compound 5 with a CO molecule trapped in the cavity was isolated.…”