5890 series 2 mass detector

Reagents were used as purchased without further purification. Solvents (EtOAc, DMF, CH₂Cl₂, toluene, MeOH and CH₃CN) were stored over molecular sieves. THF was refluxed with sodium/benzophenone and hexane was dried by distillation and stored over CaCl₂. TLC was performed on precoated silica gel polyester plates (0.25 mm thickness) with a UV fluorescence indicator 254 (Polychrom SI F254). Chromatographic separations were performed on silica gel columns by flash (Kieselgel 40, 0.040–0.063; Merck) chromatography. Melting points were determined on a Buchi 510 apparatus and are uncorrected. ¹H NMR and ¹³C NMR spectra were recorded in CDCl₃, CD₃OD, DMSO-D₆ or Acetone-D₆ on a Bruker WP 200-SY spectrometer at 200/50 MHz or a Bruker SY spectrometer at 400/100 MHz. Chemical shifts (δ) are given in ppm downfield from tetramethylsilane and coupling constants (J values) are in Hertz. IR spectra were run on a Nicolet Impact 410 Spectrophotometer. A hybrid QSTAR XL quadrupole/time of flight spectrometer was used for HRMS analyses. GC-MS spectra were performed using a Hewlett-Packard 5890 series II mass detector. A Helios-α UV-320 from Thermo-Spectronic was used for UV spectra.