To a stirred, ice-cold solution of methyl 4-phenylpiperidine-4-carboxylate hydrochloride (983 mg, 3.8 mmol) and i-Pr2NEt (1.88 mL, 10.5 mmol) in CH2Cl2 (25 mL) was added 2-adamantyl chloroformate (750 mg, 3.5 mmol). The ice bath was allowed to melt and the mixture was stirred overnight at rt. The mixture was diluted with ether (150 mL), washed with 5% aq HCl (2×30 mL) and satd aq NaHCO3 (30 mL) and dried over MgSO4. Removal of the solvent left the crude product (1.37 g, 99%) as a white solid. A 40-mg portion was purified by prep HPLC to afford the title compound (32 mg). LC-MS Method 1 tR=2.4 min, m/z=398, 1H NMR (CDCl3) 1.58 (m, 2H), 1.70-2.10 (14H), 2.56 (d, 2H), 3.10 (br d, 2H), 3.68 (s, 3H), 4.08 (d, 2H), 4.83 (s, 1H), 7.27 (m, 1H), 7.36 (m, 4H).
