Phenol → N-(tert-butoxycarbonyl)piperidine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Sodium hydride (Aldrich, 2 g, 50 mmol) was added to a solution of 4-(methylsulfonyl)hydroxy-1-piperidinecarboxylic acid, 1,1-dimethylethyl ester of Example 14, B (10 g, 25 mmol) and the phenol from part 2 (5.5 g, 50 mmol) dissolved in dimethylformamide (60 mL) at 25° C. and under N2. The mixture was stirred and heated to 80° C. for 16 hours. After this time, the solvent was removed by roto-evaporation, followed by taking the residue up in ethyl acetate (150 mL) and H2O (100 mL). The layers were separated and the aqueous was extracted via ethyl acetate (2×-150 mL). The organics were washed with saturated K2CO3 (2×-100 mL), H2O (1×-150 mL), and brine (1×-150 mL), then dried over Na2SO4, filtered, and concentrated to afford a crude oil. The oil was purified on silica gel to give 10 g of the N-boc piperidine as a clear oil. 1H NMR and mass spectroscopy was consistent with the desired compound.

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