Due to the inherent difficulties in achieving a defined and exclusive formation of multicomponent assemblies against entropic predisposition, we present the rational assembly of a heteroleptic [PdLL] coordination cage achieved through the geometric complementarity of two carefully designed ligands, L and L. With Pd(II) cations as rigid nodes, the pure distinctly angular components readily form homoleptic cages, a [PdL] strained helical assembly and a [PdL] box-like structure, both of which were characterized by X-ray analysis. Combined, however, the two ligands could be used to cleanly assemble a cis-[PdLL] cage with a bent architecture. The same self-sorted product was also obtained by a quantitative cage-to-cage transformation upon mixing of the two homoleptic cages revealing the [PdLL] assembly as the thermodynamic minimum. The structure of the heteroleptic cage was examined by ESI-MS, COSY, DOSY, and NOESY methods, the latter of which pointed toward a cis-conformation of ligands in the assembly. Indeed, DFT calculations revealed that the angular ligands and strict Pd(II) geometry strongly favor the cis-[PdLL] species. The robust nature of the cis-[PdLL] cage allowed us to probe the accessibility of its cavity, which could be utilized for shape recognition toward stereoisomeric guests. The ability to directly combine two different backbones in a controlled manner provides a powerful strategy for increasing complexity in the family of [PdL] cages and opens up possibilities of introducing multiple functionalities into a single self-assembled architecture.

Monoaddition of Grignard reagents, in particular tri(organo)silylmethylmagnesium chlorides, to [60]fullerene took place smoothly in the presence of dimethylformamide to produce (organo)(hydro)[60]fullerenes, C60R(1)H, in good yield (up to 93% isolated yield). The hydrofullerene was then deprotonated to generate the corresponding anion, C60R(-), which was then alkylated to obtain 58pi-electron di(organo)[60]fullerenes, C60R(1)R(2), in good to high yield (up to 93% overall yield). The two-step methodology provides a wide variety of 1,4-di(organo)[60] fullerenes bearing the same or different organic addends on the [60] fullerene core. By changing the addends, one can control the chemical and physical properties of the compounds at the molecular and bulk levels.

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A mechanism for the regioselective silaboration of terminal allene by a palladium catalyst has been studied theoretically. The overall reaction scheme has been examined in particular to determine the mechanism of the regioselectivity. The present catalytic reaction is exothermic and the rate-determining step is the insertion of allene into the Pd-B bond of the Pd complex. σ-Allylic and π-allylic complexes exist as intermediates and play an important role in the regioselectivity. Selective insertion of the unsubstituted CdC bond into the Pd-B bond produces the most stable σ-allylic complex, which converts to the π-allylic complex while maintaining the Pd-O coordination. The selective formation of the specific σ-allylic complex and the large activation barrier between two isomeric π-allylic complexes dominantly determines the regioselectivity of the present reaction. The major-product complex is less stable than the minor-product complex, and therefore kinetic control is predominant in the present reaction.

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