Open fullerene

T. Jarrosson, G.-W. Wang, M. D. Bartberger, G. Schick, M. Saunders, R. J. Cross, K. N. Hock, Y. Rubin, Insertion of Helium and Molecular Hydrogen Inside an Open Fullerene , manuscript in preparation. 

Opened fullerenes, 12 232 Open-end spinning, cotton yarn, 8 17 Open-head drums, 18 8 Open-hearth furnace, 12 320 21 408 Open-hearth steelmaking process, 16 150-151... 

Scheme 11.4 Photochemical reaction of 14 with singlet oxygen, leading to the cluster opened fullerene 19. (i) O2 hv, benzene (II) [2+2] cycloreversion, keto-enol tautomerization.

This model would be made more tangible if the 3D ring (or open fullerenes) seen... 

The H NMR spectra of bis(organo)fullerenes 11-15 did not substantially differ from the spectra of corresponding precursory azides 1-5 and monoorganofullerenes 6-10. At that the signals for the protons of the groups directly bonding to the N atom were slightly shifted downfield that is characteristic feature for all 5,6-open fullerene derivatives (Fig. 3). 

In a number of groundbreaking explorations,46 Wudl, Hummelen, and coworkers showed that photoinduced [2 + 2] cycloaddition of singlet oxygen to one of the electron-rich enamine-type double bonds of azahomo [60] fullerene derivative 53 (Scheme 1.8), followed by decomposition of the 1,2-dioxetane intermediate (not shown), led to ketolactam ( )-54, the first cluster-opened fullerene with a free orifice.153 Under synthetic conditions mimicking events observed in the gas phase,154 acid-induced loss of 2-methoxyethanol from... 

Whitener, K.E., Frunzi, M., Iwamatsu, S. et al. (2008) Putting ammonia into a chemically opened fullerene. Journal of the American Chemical Society, 130, 13996-13999. 

The need to prepare fullerene derivatives for possible applications to medicine and material sciences resulted in the development of novel synthetic methods for the functionalization of Cso. R. Pellicciari et al. reacted Ceo with carboalkoxycarbenoids generated by the Rh2(OAc)4-catalyzed decomposition of a-diazoester precursors. This reaction was the first example of a transition metal carbenoid reacting with a fullerene and the observed yields and product ratios were better than those obtained by previously reported methods. The reaction conditions were mild and the specificity was high for the synthesis of carboalkoxy-substituted[6,6]-methanofullerenes. When the same reaction was carried out thermally, the rearranged product (the [6,5]-open fullerene) was the major product. 

Fig. 4. Structure and space-fiUing representation of the hypothetical ring-opened fullerene 15. Rendering options are the same as in Scheme 3...

An X-ray crystal structure analysis on 219 showed that the ethylene bridge acted as an j -handle to the cobalt and, more interestingly, that the cobalt has oxidatively inserted into the C-C bond of a six-membered ring of the C6o> thus giving rise to a tare opened fullerene derivative (Figure 49). 

SCHEME 32 Photolysis of C O, leading to the [5,6] open fullerene oxide 76 (oxidoannulene). 

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