Norcamphor → 1'-(Bicyclo[2.2.1]heptan-2-yl)spiro[indene-1,4'-piperidine]-3-carboxylic acid

Participants

Reaction Steps

A mixture of compound (D1) (0.020 g, 0.058 mmol), titanium (IV) isopropoxide (0.052 mL, 0.174 mmol), and (1R,4S)-bicyclo[2.2.1]heptan-2-one (3 eq) was stirred at room temperature for 18 h in dichloroethane (0.5 mL). Sodium triacetoxyborohydride (0.012 g, 0.058 mmol) was added and stirred at room temperature for 1 h. The solvent was evaporated and 6N NaOH (0.5 mL) and methanol (1 mL) was added and then triturated to form a white solid. The solid was washed with methanol (1 mL) and EtOAc (1 mL). The filtrate was concentrated under reduced pressure to afford the crude product which was purified by reverse phase preparative HPLC to afford 1′-(bicyclo[2.2.1]heptan-2-yl)spiro[indene-1,4′-piperidine]-3-carboxylic acid (Compound No. 48) (0.002 g). LC/MS (10-90% over 3 min with 0.9% FA) m/z 324.1 (M+1), Rt 1.9 minutes.

Provenance & Evidence