A Unified Strategy for Exceptionally High Diastereoselectivity in the Photochemical Ring Closure of Chiral Diarylethenes

Abstract

Hilfreiche Umarmung: Die photochemische Cyclisierung von Diarylethenen mit zwei chiralen Seitenarmen verlief unter UV‐Bestrahlung mit bis zu 100 % de (siehe Schema). Die Einführung chiraler Seitenarme an den zu verknüpfenden Kohlenstoffzentren ist eine allgemeine Strategie für hoch diastereoselektive Diarylethen‐Cyclisierungen.

Enantioselective Photochromism of Diarylethenes in Human Serum Albumin

“…We have focused our efforts on achieving high diastereoselectivity in the photochromism of diarylethenes with the aid of chiral factors such as asymmetric stereogenic carbon atoms or an axially or facially chiral unit, introduced within the molecules themselves 2. So far, we have achieved completely diastereoselective ring‐closing reactions with several compounds 2a,b,d. However, although the highly enantioselective photochromic reactions of diarylethenes in a chiral crystalline state have been reported,3 those in solution have yet to be achieved 4…”

Chiral Photoresponsive Tetrathiazoles That Provide Snapshots of Folding States

“…A number of asymmetric reactions including diastereoselective [12,13,23] and enantioselective [24] electrocyclizations have been reported for diarylethenes in solutions, crystals, and supramolecular assemblies. These diarylethenes often tether chiral side units or adopt helicene structures to induce a chiral structure in the backbone, mainly by repulsive intramolecular interactions.…”