Carbon Monoxide Inside an Open‐Cage Fullerene

Abstract

Im Ball: Der endohedrale Kohlenmonoxidkomplex eines [60]Fullerenderivats mit geöffnetem Käfig wird durch Insertion von CO durch die Öffnung hergestellt. Das Vorliegen von CO im C60‐Käfig bestätigen massenspektrometrische sowie 13C‐NMR‐ und IR‐spektroskopische Untersuchungen. Unter Umgebungsbedingungen setzt das Produkt CO frei, wobei eine Mischung aus dem endohedralem Wasserkomplex und dem leerem Käfig zurückgewonnen wird.

Solid State Physicochemical Properties and Applications of Organic and Metallo- Organic Fullerene Derivatives

“…In some cases some of the fullerene carbons are removed rather than substituted, resulting in socalled open-cage fullerenes where functionalization is accompanied by partial disruption of the carbon backbone. The carbon cage is "opened" by successive chemical reactions referred to collectively as "fullerene surgery", leading to covalent linking of heterospecies and even oligomers to adjacent carbon atoms of the parent fullerene [42,43,44,45,46].…”

Synthesis of Open‐Cage Fullerenes Containing a H‐Bond between the Encapsulated Water Molecule and the Amide Moiety on the Rim of the Orifice

“…They are perfect molecular containers for small molecules and atoms with a suitable size. [1][2][3][4][5] A number of supramolecular systems have been reported by inserting various molecules into the cavity of open-cage C 60 derivatives such as H 2 , [6,7] H 2 O, [8][9][10] O 2 , [11,12] HF, [13,14] HCN, [15] CO, [15,16] CO 2 , [17] NH 3 , [18] CH 4 , [19] HCCH, [20] and MeOH [21] . Among them water is one of the most well-known guest molecule.…”

Encapsulation of Formaldehyde and Hydrogen Cyanide in an Open‐Cage Fullerene

“…The trapped HCN displays as harp singlet at d = À4.37 ppm (d = 3.78 ppm for free HCN), which broadens at À90 8C, to imply fast rotation of HCN molecule inside the cage on the NMR timescale. [20,22] Meanwhile, the CNs tretching frequency for HCN@2 (2087cm À1 ;t aken in chlorobenzene) is red-shifted merely 8cm À1 from free HCN (2095 cm À1 ), suggesting little interactions betweene ncaged HCN and fullerene core.…”

“…Komatsu et al subsequently prepared an ew derivative containing al arger orifice, which encapsulated H 2 quantitatively. [14] Up to now,n obleg ases (He, Ar, Kr), [13,15,16] N 2 , [15] H 2 , [13,14,15,17,18] H 2 O, [18,19] CO, [15,20] NH 3 , [21] CH 4 , [22] and HF [23] molecules have been effectively stored inside the open-cage fullerenes,a nd completion of "molecular surgery" [24] to reform the pristine C 60 cage was achieved for He@C 60 , [16] H 2 @C 60 , [17a] and H 2 O@C 60 . [19b] Yett he incorporation of organic compounds bearing functional groupsh as not been reported.…”

“…It is noteworthy that the far upfieldr esonance at d = À11.30 ppm is attributed to the encapsulatedw ater protons, which is shielded by 12.82 ppm compared to free water (d = 1.52 ppm).U nusual chemicals hifts for the endohedral nuclei have been previously observedb yN MR spectroscopy,o wing to the strong magnetic shieldinge ffect by the p-electron shell of the fullerene cage. [18][19][20][21][22][23]27] The fraction of endohedralw ater molecules can be estimated by comparing its integral value with the 1 H signal at d = 8.56 ppm. The filling factor varies depending on the experimentalc onditions such that the ratio of H 2 O@2 decreased to 25 %b yheating the toluenes olution over molecular sieves, but it reached 85 %w hen the solution was heated in the presence of trace water.N otably,t he water-inclusion behavioro fo pen-cage fullerenes was previously shown also depending on the polarity of solvents.…”