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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Interplay between anti-anti and syn-anti conformations of thiourea modulating ON-OFF catalysis
1School of Chemistry, Indian Institute of Science Education and Research Thiruvananthapuram (IISER-TVM), Thiruvananthapuram 695551, India. soumende@iisertvm.ac.in.
Abstract:
The design, synthesis and operation of a readily accessible two-state switch are demonstrated. The switch initially exists in an intramolecularly hydrogen-bonded self-locked state, as evidenced by the solution-state NMR and solid-state structure. The switch can be reversibly altered between anti-anti and syn-anti conformations by adding and removing Cu+ ions, as evidenced by the NMR and crystallographic study. The anti-anti form was found to be catalytically active in the Michael addition reaction, whereas the syn-anti form was catalytically inactive.
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