Related Experiment Video
Updated: May 7, 2026

Synthetic Methodology for Asymmetric Ferrocene Derived Bio-conjugate Systems via Solid Phase Resin-based Methodology
Published on: March 12, 2015
Asymmetric photoreaction of a diarylethene in hydrogen-bonded cocrystals with chiral molecules
Tomohiro Ichikawa1, Masakazu Morimoto, Masahiro Irie
1Department of Chemistry and Research Center for Smart Molecules, Rikkyo University, 3-34-1 Nishi-Ikebukuro, Toshima-ku, Tokyo 171-8501, Japan. iriem@rikkyo.ac.jp.
Abstract:
A photochromic diarylethene having 2-methyl-4-pyridyl groups formed chiral cocrystals with (R)- or (S)-1,1'-bi-2-naphthol (BINOL). X-ray crystal structure analysis revealed that the diarylethene forms O-H···N type hydrogen bonds with BINOL and the central hexatriene moiety is fixed in P- or M-helix conformation in the cocrystals. The diarylethene molecules underwent reversible cyclization reactions in the single-component crystal as well as in the cocrystals upon alternate irradiation with ultraviolet (UV) and visible light. In the chiral cocrystals, a highly enantioselective photocyclization reaction took place owing to the conformational confinement.
More Related Videos
Related Concept Videos
Diels–Alder Reaction Forming Cyclic Products: Stereochemistry
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation
Thermal Electrocyclic Reactions: Stereochemistry
Selection Rules: Thermal Activation
Conjugated systems containing an even number of π-electron pairs undergo a conrotatory ring closure. For example, thermal electrocyclization of (2E,4E)-2,4-hexadiene, a conjugated diene containing two π-electron pairs, gives trans-3,4-dimethylcyclobutene.
Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
Diels–Alder Reaction Forming Bridged Bicyclic Products: Stereochemistry

