Entry Reaction conditions Time Yield (%) (a) 1 NCS, NaHC[O.sub.3], EtOAc 16 h 43 2 [([Bu.sub.3]Sn).sub.2]O, t-BuOCl, DCM [36] 16 h 11 3 NaOCl, [Et.sub.3]N, DCM 16 h 26 4 NCS, [K.sub.2]C[O.sub.3], EtOAc, [H.sub.2]O 16 h 49 5 CuS[O.sub.4] x 5[H.sub.2]O, L-Ascorbate, 12 h 30 NaHC[O.sub.3], t-BuOH, [H.sub.2]O [37] 6 NaI,
2,6-Lutidine, t-BuOCl, dioxane [38] 12 h 30 7 HTIB, C[H.sub.3]CN [39] 12 h 0 8 NBS, [Et.sub.3]N, DMF [40] 18 h 1 9 Cr[O.sub.2], C[H.sub.3]CN [41] 12 h 18 (a) Determined by analysis of the crude reaction mixture by analytical LC/MS.