Department of Chemistry and Biomolecular Sciences and Centre for Advanced Materials Research (CAMaR), University of Ottawa, Ottawa, ON, K1N 6N5, Canada.
Universidad Nacional de Córdoba, Facultad de Ciencias Químicas, Ciudad Universitaria, X5000HUA, Córdoba, Argentina.
Photochem Photobiol Sci. 2022 Aug;21(8):1473-1479. doi: 10.1007/s43630-022-00237-9. Epub 2022 May 18.
Selective semi-oxidation of tetrahydroisoquinoline (THIQ) leads to a valuable dihydroisoquinoline (DHIQ) derivative via singlet oxygen photooxidation process. Typical photosensitisers (i.e., Ru complexes) can activate the reaction even under heterogeneous conditions that facilitate catalyst separation and reusability. In contrast to DHIQ, THIQ acts as an efficient singlet oxygen quencher driving the reaction selectivity. The reaction can also be facilitated by semiconductor catalysts such as MoCo@GW, a glass wool-based catalyst that is easy to separate and reuse and compatible with flow photochemistry. Its role is to mediate the formation of isoquinoline (IQ) and thus an in situ-generated singlet oxygen catalyst. Laser flash photolysis with NIR detection provides proof of the singlet oxygen mechanism proposed and rate constants for the key steps that mediate the oxidation.
通过单线态氧光氧化过程，选择性半氧化四氢异喹啉（THIQ）可得到有价值的二氢异喹啉（DHIQ）衍生物。典型的光敏剂（例如 Ru 配合物）即使在有利于催化剂分离和可重复使用的多相条件下也能激活反应。与 DHIQ 不同，THIQ 是一种有效的单线态氧猝灭剂，可驱动反应选择性。该反应还可以通过半导体催化剂（例如 MoCo@GW）来促进，MoCo@GW 是一种基于玻璃棉的催化剂，易于分离和重复使用，并且与流动光化学兼容。它的作用是介导异喹啉（IQ）的形成，从而原位生成单线态氧催化剂。使用 NIR 检测的激光闪光光解为所提出的单线态氧机制以及介导氧化的关键步骤的速率常数提供了证据。
