O[CH:2]([C:4]1[CH:17]=[CH:16][C:7]2[CH:8]=[C:9]([C:11]([O:13][CH2:14][CH3:15])=[O:12])[S:10][C:6]=2[CH:5]=1)[CH3:3].C1(P([N:32]=[N+:33]=[N-:34])(C2C=CC=CC=2)=O)C=CC=CC=1.C1CCN2C(=NCCC2)CC1.[N-]=[N+]=[N-]>C1(C)C=CC=CC=1>[N:32]([CH:2]([C:4]1[CH:17]=[CH:16][C:7]2[CH:8]=[C:9]([C:11]([O:13][CH2:14][CH3:15])=[O:12])[S:10][C:6]=2[CH:5]=1)[CH3:3])=[N+:33]=[N-:34]
To a solution of ethyl 6-(1-hydroxyethyl)-1-benzothiophene-2-carboxylate (2.0 g, 8.06 mmol) in toluene (30 mL) was added diphenylphosphorylazide (2.64 g, 9.58 mmol), then DBU (1.31 mL, 8.79 mmol) dropwise. After 24 h, added more azide (0.5 mL) and DBU (0.3 mL) to the thick solution. After an additional 24 h, the reaction mixture was concentrated and purified via column chromatography yielding the desired product (1.77 g, 80.4% over two steps). 1H NMR (CDCl3, 600 MHz) δ 8.03 (d, J=0.9 Hz, 1H), 7.87 (d, J=8.2 Hz, 1H), 7.81 (m, 1H), 7.36 (dd, J=8.2, 0.9 Hz, 1H), 4.75 (q, J=6.8 Hz, 1H), 4.40 (q, J=7.3 Hz, 2H), 1.58 (d, J=6.8 Hz, 3H), 1.41 (t, J=7.3 Hz, 3H). MS: cal'd 276 (MH+), exp 276 (MH+).
Loading…
