Fig. 4. Mechanistic experiments: (A) [HE] = 1 × 10−4 M, [NaOAc] = saturated in DMSO (please see the ESI for details†); (B) excitation wavelength = 400 nm, [HE] = 1 × 10−3 M, [NaOAc] = saturated in DMSO; (C) excitation wavelength = 373 nm, [HE] = 1 × 10−4 M, [NaOAc] = saturated in DMSO; (D) isolated yield on 0.02 mmol scale; (E) NMR yields using 1,1,2,2-tetrachloroethane as the internal standard (product 59 was isolated to confirm the structure).
