Spontaneous chiral resolution and hierarchical directing effects of two-winged propeller-like SDAs on the construction of noncentrosymmetric iodoargentates/iodocuprates

Abstract

Directed by in situ benzylated pyridine derivatives with potential conformational chirality, four inorganic–organic hybrids, [BCP]₂[Ag₄I₆] (1), [BCP][Cu^I₂Cu^III₅]·2H₂O (2), [BQL][Ag₄I₅] (3), [BQL]₂[Cu₅I₇] (4) (BCP⁺ = N-benzyl-4-cyanopyridinium, BQL⁺ = N-benzyl-quinolinium) have been synthesized solvothermally. The contrast between spontaneous chiral resolution for BCP⁺ in 1 and 2 and racemic BQL⁺ aggregates in 3 and 4, and remarkable structural correlations between organic and inorganic species exhibit interesting chiral structure directing effects, which are mainly attributed to the variation of organic motif, substituent, and consequently flexible supramolecular assemblies, as well as hierarchical matching ability between inorganic and organic species. 1 also exhibits second harmonic generation (SHG) responses in both visible and ultraviolet regions.