Compound 13

View in PubChem | MDL Molfile | ChemDraw

InChIKey NWWBDJLOOWNMNH-CWIKABRRSA-N

Synthetic procedure: See article for the definitive version of this procedure and for full experimental details.

500 mg (1.55 mmol, 1 eq.) sulfite 12 was dissolved in DMF (37 mL) and treated with 1.14 mL (4.64 mmol, 3 eq., 20% solution in water) LiN₃. The reaction mixture was stirred at 130 °C for 2.5 h, cooled to room temperature and diluted with H₂O (150 mL). The reaction mixture was extracted with EtOAc (3 × 50 mL) and the combined organic layers were subsequently washed with H₂O (3 × 100 mL), 10% aq. LiCl (100 mL) and brine (100 mL). The organic layer was dried over MgSO₄, filtered and concentrated in vacuo. The crude product was purified by flash column chromatography (hexanes:EtOAc = 3:1) to yield 390 mg (1.29 mmol, 83%) azido alcohol 13 as a clear oil (one spot on TLC). TLC (hexanes:EtOAc = 6:4), R_f = 0.50 (UV, CAM). ¹H NMR (CDCl₃, 300 MHz): δ= 7.45–7.31 (m, 5H), 5.95–5.79 (dd, J=8.0, 18.8 Hz, 1H), 5.61–5.47 (m, 1H), 5.29–5.16 (m, 3H), 4.27–4.02 (m, 2H), 3.82–3.69 (m, 1H), 3.15 (dd, J=4.2, 15.2 Hz, 1H), 2.75–2.54 (m, 1H), 2.40–2.22 (m, 2H). ¹³C NMR (CDCl₃, 75 MHz): δ= 158.8, 136.0, 130.1, 130.0, 129.3, 128.7, 128.5, 128.3, 128.2, 77.0, 68.3, 63.9, 54.3, 49.5, 28.8. IR (Diamond-ATR, neat) ν_max: 3376, 2930, 2099, 1663, 1417, 1258, 1210, 1132, 1066, 987, 733, 696 cm^-1. [α]²⁵ _D – 11.6° (c= 0.43, CHCl₃). HRMS (ESI) calcd for C₁₅H₁₈N₄O₃ [M+Na]⁺: 325.1277; found: 325.1271.