[CH3:1][O:2][C:3](=[O:16])[CH2:4][O:5][C:6]1[CH:15]=[CH:14][CH:13]=[C:12]2[C:7]=1[CH2:8][CH2:9][CH2:10][O:11]2.C[Si]([N:21]=[C:22]=[S:23])(C)C.FC(F)(F)C([O-])=O.FC(F)(F)C([O-])=O.C1([I+2])C=CC=CC=1>FC(F)(F)C(O)C(F)(F)F>[CH3:1][O:2][C:3](=[O:16])[CH2:4][O:5][C:6]1[CH:15]=[CH:14][C:13]([S:23][C:22]#[N:21])=[C:12]2[C:7]=1[CH2:8][CH2:9][CH2:10][O:11]2A stirred solution of (chroman-5-yloxy)-acetic acid methyl ester (2.1 g, 9.4 mmol) and trimethylsilyl isothiocyanate (2 mL, 14.1 mmol) in 30 mL 1,1,1,3,3,3-hexafluoro-propan-2-ol under a N2 atmosphere was treated with phenyliodine(III) bis(trifluoroacetate). The reaction mixture stirred at room temperature for 1 h and concentrated in vacuo. Purification by flash column chromatography (gradient elution: 10% EtOAc/hexanes to 40% EtOAc/hexanes) gave the title compound (1.3 g, 50%) as a pale yellow solid. 400 MHz 1H NMR (DMSO-d6) δ 7.31 (d, 1H, J=8.8 Hz), 6.54 (d, 1H, J=8.8 Hz), 4.83 (s, 2H), 4.21 (t, 2H, J=4.9 Hz), 3.64 (s, 3H), 2.60 (t, 2H, J=6.4 Hz), 1.89 (m, 2H).
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