Regioselective access to 3^I-O-substituted-β-cyclodextrin derivatives (original) (raw)

2009, Chemical Communications

Experimental procedures, 1 H and 13 C NMR data, identification of monosubstituted β-cyclodextrin regioisomers, NMR spectra for compounds 6a, 6b, 13a and 13b as specific and representative examples. I) Experimental procedures and NMR data : General: All solvents and reagents were purchased from commercial sources and used without further purification. Reactions were monitored by thin-layer chromatography (TLC) on a plate of silica gel 60 F 254 (E. Merck, Darmstadt, Germany) and detection by charring with sulfuric acid. Columns chromatography were performed on silica gel 60 (0.063-0.200 mm, E. Merck). LC-MS analyses were performed on a Waters 2695 Alliance coupled with a single quadripole mass spectrometer ZQ (Waters-Micromass, Manchester, UK) equipped with an electrospray ion source (ESI-MS). The composition of the mobile phase varied during the run according to a linear gradient as follows: A-B: 0 min (20:80, v/v), 0-50 min (50:50, v/v) at a flow rate of 1 mL/min. Compounds were loaded on a Alltech Carbohydrate ES 5u (5μm particle size, 250 mm x 4.6 mm) column using a sample injection volume of 20 µL (water solutions at 1 g/L for the compounds). The effluent was flow-split