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Chemical reduction of highly-twisted 9,10,11,20,21,22-hexaphenyltetrabenzo[a,c,l,n]pentacene (C74H46, 1) was investigated using Li and Cs metals as the reducing agents. The Cs-induced reduction of 1 in the presence of 18-crown-6 ether enabled the isolation of a solvent-separated ion pair (SSIP) with a “naked” monoanion. Upon reduction with Li metal, a double reductive dehydrogenative annulation of 1 was observed to afford a new C74H422– dianion. The latter was shown to undergo a further reduction to C74H424– without additional core transformation. All products were characterized by single-crystal X-ray diffraction and spectroscopic methods. Subsequent in-depth theoretical analysis of one vs. two and four electron uptake by 1 provided insights into how the changes of geometry, aromaticity and charge facilitated the core transformation of twistacene observed upon two-fold reduction. These experimental and theoretical results pave the way to understanding of the reduction-induced core transformations of highly twisted and strained π-systems. 

Establishing a strategy for realizing programmed self-assembly is critical in manufacturing materials with functional hybrid structures. In this work, we introduce a robust methodology for enabling multi-component self-assembly using the concept of chirality-directed self-assembly. A specific combination of heterochiral Zn(II) methylene bis(oxazoline) (BOX) complexes can be selectively generated when combinations of enantiomers of chiral BOX ligands are mixed in the presence of Zn(Oac)2. The resulting Zn(II) BOX complexes, unlike non-covalent bonds, are highly stable and stay intact at elevated temperatures, yet can be reversibly disintegrated under mild conditions using EDTA. This approach can be easily applied to multi-functionalize various solid supports enabling the one-pot generation of multi-functional hybrid structures. 

Resin-immobilized catalysts were prepared through chirality-driven self-assembly. The method allows the resin-immobilized catalyst to be regenerated under mild conditions and in situ catalyst exchange to be carried out quantitatively. The uniqueness of the methodology was demonstrated by the preparation of a catalyst for TEMPO oxidation as well as a two-step sequential TEMPO oxidation/aldol condensation sequence enabled by facile catalyst exchange. 

A strategy to build Janus dendrimers via the chirality-directed self-assembly of heteroleptic Zn( ii ) BOX complexes is reported. The method allows quantitative synthesis of Janus dendrimers in situ without the need for purifications. Each dendritic domain of the Janus dendrimers can be recycled upon disassembly at the focal point.