Flash purification system

To a 10 mL MeOH solution containing 100 mg (0.196 mmol) of 10 was added 149 mg (0.432 mmol; 50% purity) mCPBA. The resultant solution was heated at 70 °C in a microwave reactor for 20 min. The conversion of 10 to 11 was followed by HPLC. The reaction mixture was evaporated to dryness using rotary evaporator under vacuum. The crude 11 was dissolved in 1:1 MeOH:H₂O and purified using Biotage Flash Purification System (Charlottesville, VA, USA) to yield 14 mg (13.2%). ¹H NMR (DMSO-d₆): δ 2.23 (t, 2H, J = 6.2 Hz), 2.79 (t, 2H, J = 5.7 Hz), 3.46–3.53 (m, 15H), 3.57 (t, 2H, J = 6.2 Hz), 3.89 (s, 3H), 8.08–8.14 (m, 4H). HRMS (ES⁺): C₁₉H₂₈INNaO₉ (M+Na)⁺ Calcd: 564.0707 Found: 564.0762. HPLC t_R = 5.0 min.

All chemicals were purchased from Sigma-Aldrich, Acros Chemicals, Fluorochem or Alfa Aesar and used without further purification unless otherwise stated. Anhydrous acetonitrile was obtained from a MBraun SPS800 solvent purification system unless otherwise stated. Flash column chromatography was performed using Biotage Flash Purification system. ¹H NMR and ¹³C NMR spectra were measured on a Bruker Avance 500 NMR spectrometer and Bruker Avance DPX400 spectrometer. ¹H NMR and ¹³C NMR spectra are reported as chemical shifts in ppm downfield from TMS and J values are given in Hertz. ³¹P NMR spectra were recorded on Bruker Avance DPX400 spectrometer or Bruker Avance 500 NMR spectrometer and are reported in chemical shifts downfield from 85% H₃PO₄. Reverse phase HPLC was performed on a system comprising of a Dionex P680 pump and a Dionex UVD170U detector unit.