Self-driven carbon atom implantation into fullerene embedding metal–carbon cluster

Abstract

Hundreds of members have been synthesized and versatile applications have been promised for endofullerenes (EFs) in the past 30 y. However, the formation mechanism of EFs is still a long-standing puzzle to chemists, especially the mechanism of embedding clusters into charged carbon cages. Here, based on synthesis and structures of two representative vanadium–scandium–carbido/carbide EFs, VSc 2 C@ I h (7)-C 80 and VSc 2 C 2 @ I h (7)-C 80 , a reasonable mechanism—C 1 implantation (a carbon atom is implanted into carbon cage)—is proposed to interpret the evolution from VSc 2 C carbido to VSc 2 C 2 carbide cluster. Supported by theoretical calculations together with crystallographic characterization, the single electron on vanadium (V) in VSc 2 C@ I h (7)-C 80 is proved to facilitate the C 1 implantation. While the V=C double bond is identified for VSc 2 C@ I h (7)-C 80 , after C 1 implantation the distance between V and C atoms in VSc 2 C 2 @ I h (7)-C 80 falls into the range of single bond lengths as previously shown in typical V-based organometallic complexes. This work exemplifies in situ self-driven implantation of an outer carbon atom into a charged carbon cage, which is different from previous heterogeneous implantation of nonmetal atoms (Group-V or -VIII atoms) driven by high-energy ion bombardment or high-pressure offline, and the proposed C 1 implantation mechanism represents a heretofore unknown metal–carbon cluster encapsulation mechanism and can be the fundamental basis for EF family genesis.

Recent advances in supramolecular fullerene chemistry

“…10 The first category includes mono-, di-, and trimetallofullerenes, 104–109 as well as cluster metallofullerenes 110 ( e.g. oxide clusters, 103 nitride clusters, 111–113 cyano clusters, 114 sulfide clusters, and carbide clusters), 10,97–99,115–120 while the second category includes H 2 , noble gases, 121 water and other non-metal guests. 10,100 (Fig.…”

The formation mechanism of Sc-based metallofullerenes: a molecular dynamics simulation study

“…25 In 2014, Duck et al proposed that charge transfer is a principal factor that guides the bottom-up formation of endohedral mono-metallofullerenes. 26 Recently, Guan et al 27 and Yao et al 28 found that as-formed metallofullerenes can capture atomic carbon and its dimer.…”

Transition Metal/Lanthanide-Nitrogen Double Bonds Co-stabilized in a Carbon Cage

“…Different from NCFs, metal carbido clusterfullerenes offer an opportunity to stabilize metal-nonmetal double bonds, which however require involvement of nonrare earth metals, including transition metals (titanium (Ti), vanadium­(V)) or actinide metal U with higher valence states than +3 of most trivalent rare-earth metals. − Several metal carbido clusterfullerenes containing TiC double bonds have been identified in TiM 2 C@C 80 (M = Lu, Tb, Dy, Sc) by single-crystal X-ray diffraction, together with two M–C single bonds. ,− Instead, upon encapsulating Ti into the fullerene cage in the form of NCFs, Ti–N single bonds along with two M–N single bonds exist within TiM 2 N@C 80 (M = Sc, Y, see Scheme ). , This discrepancy results from the fact that fewer valence bonds (three) are normally required for N than those (four) for C. These reports stimulate us to involve Ti together with a lanthanide metal cerium (Ce) to construct a transition metal-lanthanide heteronuclear nitride clusterfullerene TiCeN@C 84 .…”