Axially chiral indolenine derived chromophore dimers and their chiroptical absorption and emission properties.

ABSTRACT: Yamamoto homocoupling of two chiral oxindoles led to the atropo-diastereoselective formation of an axially chiral oxindole dimer. This building block served as the starting material for the syntheses of axially chiral squaraine and merocyanine chromophore dimers. These dimers show pronounced chiroptical properties, this is, outstandingly high ECD signals (Δε up to ca. 1500 M^-1 cm^-1) as a couplet with positive Cotton effect for the P-configuration around the biaryl axis and a negative Cotton effect for the M-configuration. All investigated dimers also exhibit pronounced circularly polarised emission with anisotropy values of ca. 10^-3 cgs. Time-dependent density functional calculations were used to analyse the three contribu

SUBMITTER: Freytag E 

PROVIDER: S-EPMC9601394 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature