To a stirred solution of t-butyl-N-(1-[(9S,10S)-2-chloro-9,10-dihydro-9,10-methanoanthracen-9-ylmethyl]-4-piperidyl)carbamate produced in Example 1b (1.24 g, 2.74 mmol) in methylene chloride (15 mL) was added trifluoroacetic acid (2.11 mL, 27.37 mmol). After stirring the resulting mixture for 18 h, the reaction was concentrated to give a pale pink syrup. The syrup was dissolved in methylene chloride (100 mL), cooled to 0 C. (ice bath) and treated with 3N sodium hydroxide and extracted with methylene chloride (3×50 mL). The combined extracts was washed with 3N sodium hydroxide (2×75 mL) and brine (75 mL), dried (sodium sulfate), filtered, and concentrated to give the title compound as a white foamy glass (967 mg, 100%); mp 93°-5° C.; MS(CI); 353 (M+H); NMR (300 MHz,DMSO-d6): 1.23(br m, 2H), 1.67-1.85(br m, 2H), 2.71-3.02(br m, 5H), 3.27-3.39(br m, part. submerged, 2H), 3.66(br s, 1H), 4.42(s, 1H), 4.47(s, 1H), 7.00(m, 3H), 7.30-7.66(br m, 4H).
