反应详情

4-Hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (1.9 g, 11 mmol) is dissolved in THF (40 ml) and hydrogenated in the presence of 0.035 g Pt (5% on carbon) catalyst using 4 bar hydrogen pressure. The hydrogen uptake stops after approximately one hour. The reaction mixture is then filtered and mixed with the solution of bis-p-tolyl-carbodiimide (2.45 g, 11 mmol) in THF (30 ml). The solution is stirred under argon at room temperature for 16 hours and concentrated. The residue is chromatographed on silica gel with hexane-ethyl acetate (1:1) and the pure fractions are crystallized from ethyl acetate to afford 1.6 g of the title compound as a colorless solid, mp. 124-126° C.

1. filtrationThe reaction mixture is then filtered
2. concentrationconcentrated
3. customThe residue is chromatographed on silica gel with hexane-ethyl acetate (1:1)
4. customthe pure fractions are crystallized from ethyl acetate