Jin Y, Li S, Han Z, Yan BJ, Li HY, Dong XY, Zang SQ. Cations Controlling the Chiral Assembly of Luminescent Atomically Precise Copper(I) Clusters.
Angew Chem Int Ed Engl 2019;
58:12143-12148. [PMID:
31267660 DOI:
10.1002/anie.201906614]
[Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Indexed: 11/09/2022]
Abstract
Chiral assembly and asymmetric synthesis are critically important for the generation of chiral metal clusters with chiroptical activities. Here, a racemic mixture of [K(CH3 OH)2 (18-crown-6)]+ [Cu5 (St Bu)6 ]- (1⋅CH3 OH) in the chiral space group was prepared, in which the chiral red-emissive anionic [Cu5 (St Bu)6 ]- cluster was arranged along a twofold screw axis. Interestingly, the release of the coordinated CH3 OH of the cationic units turned the chiral 1⋅CH3 OH crystal into a mesomeric crystal [K(18-crown-6)]+ [Cu5 (St Bu)6 ]- (1), which has a centrosymmetric space group, by adding symmetry elements of glide and mirror planes through both disordered [Cu5 (St Bu)6 ]- units. The switchable chiral/achiral rearrangement of [Cu5 (St Bu)6 ]- clusters along with the capture/release of CH3 OH were concomitant with an intense increase/decrease in luminescence. We also used cationic chiral amino alcohols to induce the chiral assembly of a pair of enantiomers, [d/l-valinol(18-crown-6)]+ [Cu5 (St Bu)6 ]- (d/l-Cu5V ), which display impressive circularly polarized luminescence (CPL) in contrast to the CPL-silent racemic mixture of 1⋅CH3 OH and mesomeric 1.
Collapse