Encapsulation and Dynamic Behavior of Methanol and Formaldehyde inside Open‐Cage C₆₀ Derivatives

Abstract

Methanol (CH OH) and formaldehyde (H CO) molecules were inserted into an open-cage C derivative with a large opening, under high-pressure and high-temperature conditions in solution. Isolation of their molecular complexes in pure form was achieved by the use of recycling HPLC with Buckyprep columns. H NMR spectroscopy, single-crystal X-ray diffraction studies, and DFT calculations revealed the orientation of the encapsulated CH OH and H CO, both in solution and in the solid state, and the results show that the CH group of the CH OH and the carbonyl group of the H CO point to the bottom of the cages. Furthermore, the dynamic behavior of the CH OH and H CO were studied at the molecular level.

Synthesis and Properties of Open Fullerenes Encapsulating Ammonia and Methane

“…We were pleased to find that exposure of a sample of fullerene 1 in CDCl 3 to a 16 % aqueous ammonia solution led to an 85:15 molar ratio of NH 3 @ 1 and H 2 O@ 1 by 1 H NMR, the spectrum displaying broad peaks at −12.44 and −11.52 ppm, respectively, indicating selective encapsulation of ammonia in accord with the calculation of binding energies. In order to avoid contamination with H 2 O‐containing species, we switched to a methanolic solution of ammonia as methanol is too large to enter 1 at room temperature . To our delight, rapid formation of NH 3 @ 1 was observed by NMR although attempts to isolate NH 3 @ 1 gave only the empty open fullerene ( 1 ).…”

Synthesis of Open‐Cage [60]Fullerenes with Five Carbonyl Groups on the Rim of the 15‐Membered Orifice

“…The key reaction in most of the reported open‐cage method is the addition of singlet oxygen to form a dioxetane ring followed by ring‐opening rearrangement . Some of the open‐cage molecules have a orifice large enough to encapsulate small molecules such as CH 4 , CO 2 , HCCH and MeOH . We have reported the synthesis of several fullerene‐mixed peroxides .…”

“…[3] Some of the open-cage molecules have a orifice large enough to encapsulate small molecules such as CH 4 , [2a,4] CO 2 , [5] HCCH [6] and MeOH. [7] We have reported the synthesis of several fullerene-mixed peroxides. [8] Further reactions of these peroxides have led to various open-cage fullerene derivatives, [9] some of which are able to encapsulate small molecules including H 2 O, [10] CO [11] and H 2 O 2 .…”

[60]Fullerene‐Based Macrocycle Ligands

“…Formation of homofullerene and subsequent oxidation by singlet oxygen is the most widely used strategy. Molecules as large as methanol has been successfully put into the open‐cage C 60 derivatives prepared through this procedure . Insertion of sulfur, oxygen and nitrogen has been achieved on the rim of the orifice as in compounds 19 – 23 (Scheme ) .…”

“…Molecules as large as methanol has been successfully put into the open‐cage C 60 derivatives prepared through this procedure . Insertion of sulfur, oxygen and nitrogen has been achieved on the rim of the orifice as in compounds 19 – 23 (Scheme ) . We have reported a number of open‐cage fullerene derivatives .…”