Work

Isomer-dependent reactivity in the solid state: topochemical [4 + 4] vs. [4 + 2] cycloaddition reactions

Year: 2025

Type: article

Abstract: -acyl isomer 2 crystallized with the face-to-face arrangement of their anthracene units, with a separation of 3.8 Å between them, satisfying Schmidt's criteria, suggesting that they can undergo a topochemical [4 + 4] photocycloaddition reaction. Upon irradiation using blue light (456 nm), the isomer 2 underwent a quantitative [4 + 4] cycloaddition reaction yielding the dimer D2. However, isomer 1 did not undergo [4 + 4] cycloaddition; instead, it underwent a photochemical [4 + 2] cycloaddition with molecular oxygen, eventually yielding anthraquinone (AQ). The dimer D2 underwent a retro-cycloaddition reaction to revert back to the isomer 2. While isomers give the same product in solution-state reactions, our study establishes that isomers can react differently in the solid state and can give different products.

Source: Chemical Science

DOI: 10.1039/d5sc02327k

Authors: Anu Lal, Kana M. Sureshan

Institution: Indian Institute of Science Education and Research Thiruvananthapuram

Language: English

Topic: Crystallography and molecular interactions

Subfield: Physical and Theoretical Chemistry

Field: Chemistry

Domain: Physical Sciences

Open Access status: diamond

Funders: Arthritis National Research Foundation, Department of Science and Technology, Ministry of Science and Technology, India, Department of Higher Education, India, Ministry of Education, India

Awards: G1023563091, G4708121266, G5715463258