Table 1.
Optimization conditions. General conditions: 1a (0.2 mmol), UO2(NO3)2·6H2O (4 mol%), acid (0.2 mmol) and H2O (0.6 mmol) were stirred in solvent (2 mL) at room temperature for 24 hours under blue light (460 nm). 1H nuclear magnetic resonance (NMR) yields with CH2Br2 as the internal standard. (a) Acid (30 mmol%). (b) Isolated yields. (c) Ir[dF(CF3)ppy]2dtbpy·PF6, Ru(bpy)3Cl2·6H2O or Riboflavin tetraacetate instead of UO2(NO3)2·6H2O. (d) Without UO2(NO3)2·6H2O. (e) No light. NR = no reaction.
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