Probing intramolecular CH-π interactions in o-quinodimethane adducts of [60]fullerene using variable temperature NMR.

Several o-quinodimethane adducts of [60]fullerene were synthesized and their intramolecular aryl CH-fullerene π interactions were studied using variable temperature-NMR (VT-NMR). Evaluation of the rate constants associated with the first-order transition states for cyclohexene boat-to-boat inversions enables quantification of ΔG(‡) values for each inversion. A comparison between two constitutional isomers, only one of which is capable of intramolecular CH-π interactions, provides a lower limit of 0.95 kcal/mol for each aryl CH-fullerene π interaction.

2,5-Dichloro-thio-phene 1,1-dioxide.

The complete mol-ecule of the title compound, C(4)H(2)Cl(2)O(2)S, is generated by crystallographic twofold symmetry, with the S atom lying on the rotation axis. In the crystal, the molecules are linked by C-H⋯O hydrogen bonds..

2,3-Bis(bromo-meth-yl)-1,4-diphenyl-benzene.

In the title compound, C(20)H(16)Br(2), the terminal phenyl groups are twisted away from the central ring by approximately 55 and -125° (average of four dihedral angles each), respectively. The crystal structure is stabilized by a combination of inter-molecular and intra-molecular inter-actions including inter-molecular π-π stacking inter-actions [C atoms of closest contact = 3.423 (5) Å].

1,2-Dimethyl-4,5-diphenyl-benzene determined on a Bruker SMART X2S benchtop crystallographic system.

The title compound, C(20)H(18), has two crystallographically independent mol-ecules in the asymmetric unit. The phenyl substituents of mol-ecule A are twisted away from the plane defined by the central benzene ring by 131.8 (2) and -52.7 (3)°. The phenyl substituents of mol-ecule B are twisted by -133.3 (2) and 50.9 (3)°. Each mol-ecule is stabilized by a pair of intra-molecular C(aryl, sp(2))-H⋯π inter-actions, as well as by several inter-molecular C(methyl, sp(3))-H⋯π inter-actions.

Facile, scalable, regioselective synthesis of C3v C60H18 using organic polyamines.

[chemical structure: see text]. Organic polyamines are efficient reagents for the regioselective hydrogenation of [60]fullerene. When [60]fullerene is heated in diethylenetriamine, a known C60H18 isomer with C3v symmetry is produced and isolated in good purity without the need for chromatographic separation. The reaction can be scaled upward to multigram levels without impacting yield or quality of product.