Heterogeneous C–H Functionalization in Water via Porous Covalent Organic Framework Nanofilms: A Case of Catalytic Sphere Transmutation
نویسندگان
چکیده
Heterogeneous catalysis in water has not been explored beyond certain advantages such as recyclability and recovery of the catalysts from reaction medium. Moreover, poor yield, extremely low selectivity, active catalytic site deactivation further underrate heterogeneous water. Considering these facts, we have designed synthesized solution-dispersible porous covalent organic framework (COF) nanospheres. We used their distinctive morphology dispersibility to functionalize unactivated C–H bonds alkanes heterogeneously with high yield (42–99%) enhanced regio- stereoselectivity (3°:2° = 105:1 for adamantane). Further, fabrication catalyst-immobilized COF nanofilms via self-assembly nanospheres first time become key toward converting catalytically inactive homogeneous into effective operating This unique occurs through protrusion fibers at interface two nanospheres, transmuting spheres films without any leaching catalyst molecules. The nanofilms’ chemical functionality hydrophobic environment stabilize high-valent transient oxoiron(V) intermediate restricts site’s deactivation. These a (45–99%) degree selectivity (cis:trans 155:1; 3°:2° 257:1, cis-1,2-dimethylcyclohexane). To establish this approach’s “practical implementation”, conducted inflow (TON 424 ± 5) using fabricated on macroporous polymeric support.
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ژورنال
عنوان ژورنال: Journal of the American Chemical Society
سال: 2021
ISSN: ['0002-7863', '1520-5126', '1943-2984']
DOI: https://doi.org/10.1021/jacs.1c02425