Experimental Section

Abstract

All non-aqueous reactions were carried out using oven-dried glassware under a positive pressure of dry nitrogen unless otherwise noted. All reagents and solvents were reagent grade. Further purifications and drying by standard methods were used when necessary. Except as indicated otherwise, reactions were magnetically stirred and monitored by thin layer chromatography (TLC) using Merck silica gel 60 F254 plates and visualized by fluorescence quenching under UV light. In addition, compounds on TLC plate were visualized with a spray of 5% w/v dodecamolybdophosphoric acid in ethanol and with subsequent heating. Chromatographic purification of products (flash chromatography) was performed on E. Merck silica gel 60 (230–400 mesh). All evaporation of organic solvents was carried out with a rotary evaporator. Yields refer to chromatographically and spectroscopically pure compounds, unless otherwise stated.