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A Solid-State Intramolecular Wittig Reaction Enables Efficient Synthesis of Endofullerenes Including Ne@C₆₀ , ³ He@C₆₀ , and HD@C₆₀.

ABSTRACT: An open-cage fullerene incorporating phosphorous ylid and carbonyl group moieties on the rim of the orifice can be filled with gases (H₂ , He, Ne) in the solid state, and the cage opening then contracted in situ by raising the temperature to complete an intramolecular Wittig reaction, trapping the atom or molecule inside. Known transformations complete conversion of the product fullerene to C₆₀ containing the endohedral species. As well as providing an improved synthesis of large quantities of ⁴ He@C₆₀ , H₂ @C₆₀ , and D₂ @C₆₀ , the method allows the efficient incorporation of expensive gases such as HD and ³ He, to prepare HD@C₆₀ and ³ He@C₆₀ . The method also enables the first synthesis of Ne@C₆₀ by molecular surgery, and its characterization by crystallography and ¹³ C NMR spectroscopy.

SUBMITTER: Hoffman G

PROVIDER: S-EPMC8048630 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Highly Stable [C60AuC60]+/- Dumbbells.

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Electronic and Vibrational Absorption Spectra of NH2 in Solid Ne.

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Synthesis and Stability of Actinium-225 Endohedral Fullerenes, 225Ac@C60.

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Crystal structure of di-aqua-(3,14-diethyl-2,6,13,17-tetra-aza-tri-cyclo-[16.4.0.07,12]docosa-ne)copper(II) (3,14-diethyl-2,6,13,17-tetra-aza-tri-cyclo[16.4.0.07,12]docosa-ne)copper(II) tetra-bromide dihydrate, [Cu(C22H44N4)(H2O)2][Cu(C22H44N4)]Br4·2H2O.

Project description:The crystal structure of the new double CuII complex salt, [Cu(L)(H2O)2][Cu(L)]Br4·2H2O (L = 3,14-diethyl-2,6,13,17-tetra-aza-tri-cyclo-[16.4.0.07,12]docosane, C22H44N4) has been determined using synchrotron radiation. The asymmetric unit contains one half of a [Cu(L)(H2O)2]2+ cation, one half of a [Cu(L)]2+ cation (both completed by crystallographic inversion symmetry), two bromide anions and one water solvent mol-ecule. The CuII atom in the first complex exists in a tetra-gonally distorted octa-hedral environment with the four N atoms of the macrocyclic ligand in equatorial and two aqua ligands in axial positions, whereas the CuII atom in the second complex exists in a square-planar environment defined by the four nitro-gen atoms of the macrocyclic ligand. The two macrocyclic rings adopt the most stable trans-III configuration with normal Cu-N bond lengths from 2.016 (3) to 2.055 (3) Å and an axial Cu-O bond length of 2.658 (4) Å. The crystal structure is stabilized by inter-molecular hydrogen bonds involving the macrocycle N-H or C-H groups and the O-H groups of water mol-ecules as donor groups, and the O atoms of water mol-ecules and bromide anions as acceptor groups, giving rise to a one-dimensional network extending parallel to [100].

| S-EPMC8183443 | biostudies-literature