Surgery of fullerenes

Abstract

Recent attempts at the synthesis of endohedral fullerenes by organic reactions, so-called "molecular surgery" methods, are surveyed. The creation of an opening on the surface of fullerene cages allowed insertion of He, H(2), H(2)O, or CO within the cages. An effective route to "suture" an opening was established to realize a new endohedral fullerene, H(2)@C(60). Further development of this operation as well as the properties and reactions of H(2)@C(60) are summarized. Also the application of the encapsulated H(2) molecule as an NMR probe for the study of aromaticity of ionic fullerenes is described.

Unusual Thermal Reactivity of [W(CPh)(NCMe)(η2‐C60)(η5‐C5Ph5)] in Chlorobenzene Involving Activation of All Ligands

“…Proposed pathways for the thermal reaction of 2. (7), C8-W1 2.506(7), C15-W1 2.432(7), C22-W1 2.351(8), C29-W1 2.370(7), C36-W1 2.003(8), N1-W1 1.747(6), Cl1-W1 2.367(2), C1-C8 1.44(1), C1-C29 1.46(1), C8-C15 1.401(9), C15-C22 1.46(1), C22-C29 1.454(9), C43-C44 1.51(1), C43-C45 1.54(1), C43-C46 1.55(1), C45-C46 1.64(1), N1-C43 1.435 (9). Selected bond angles [8]: C36-W1-N1 100.4(3), C36-W1-Cl1 96.3(2), Cl1-W1-N1 101.3(2), W1-N1-C43 173.3(5), N1-C43-C44 115.7(6), N1-C43-C45 114.6(6), N1-C43-C46 114.7(6).…”

“…[6,7] Subsequent work has been extensive, and many attempts have been made to coordinate fullerenes to metals, [8] and to incorporate metal-binding groups into their structures. [9] Investigation of the reactivity of fullerene-bound organometallic compounds also becomes an attractive research topic.…”

Inelastic neutron scattering investigations of the quantum molecular dynamics of a H2molecule entrapped inside a fullerene cage

“…In addition to the increasing literature on the chemical principles [5,6,7,8,9,10,11,12], spectroscopic investigations using infra-red (IR) [3,13,14,15], inelastic neutron scattering (INS) [3,16,17] and nuclear magnetic resonance (NMR) [3,18,19] have probed the physical characteristics of these complexes. Also, heat capacity measurements have identified a small splitting of the rotational line associated with the symmetry of the crystal field, a first indication of inter-fullerene contributions to the effective cage potential [20].…”

X-ray observation of a helium atom and placing a nitrogen atom inside He@C60 and He@C70

“…However, the encapsulation level of the helium atom was quite low such as 0.15-0.4% (refs 5,6) because of the inefficiency of this physical method, although the inner 3 He atom is useful for the clarification of the internal magnetic field of fullerenes 5 . On the other hand, we have developed rational synthetic methodology [7][8][9][10][11][12][13][14][15] , so-called 'molecular surgery' 16 , and recently succeeded in the chemical syntheses of He@C 60 and He@C 70 with ca. 30% encapsulation levels in macroscopic scales.…”