Curved polyaromatic hydrocarbons

Reactions of curved polyaromatic hydrocarbon hgands like C60 with transition metals is of current interest. Oxidative addition of a strained five-membered ring of a C60-derived molecule to cobalt provides a candidate complex for the inclusion of a metal into the C60 framework [65]. 

Curved polyaromatic hydrocarbons undergo oxidative addition. A strained five-membered ring of a C60-derived molecule reacted with a CpCo fragment (Scheme 1.25) [34]. Analogously, a bowl-shaped fullerene subunit reacted with a platinum(O) complex (Scheme 1.26) [35]. 

The effect of curvature on the aromatic character of polyaromatic hydrocarbons (PAHs) can be studied by comparing planar PAHs and their curved analogues. In order to address this issue a variety of [n](2,7)pyrenophanes (n = 7-10) in which the pyrene (22) moiety is strongly distorted from planarity have been synthesized and studied45. The degree of distortion from planarity and therefore the strain in these systems is controlled by the length and type of the tether that connects the two remote ends (positions 2 and 7) of 22. 

The separation scheme for deasphaltened bitumen on silica [WOELM, activated at 140°C (4 hr)] is shown in Figure 1. The fractions obtained were loosely termed hydrocarbons. Polar I, II, and III. The IR spectra of these fractions, as shown in Figure 2, suggested that Polar I was very similar to the polyaromatic/neutral polar fraction from the API 60-based separation after removal of additional material from alumina with pure benzene. Also, simulated distillation curves for this fraction from either procedure are very similar (Figure 3). The IR spectra of the Polar II and III fractions show the presence of all the functional groups which can be distinguished in these complex mixtures and which... 

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