Hydrochloric Acid → (R)-tert-butyl 1-(2-adamantylcarbamoyl)pyrrolidin-3-ylcarbamate

Participants

Reaction Steps

A vial was charged with (R)-tert-butyl pyrrolidin-3-ylcarbamate (21 mg, 0.11 mmol) and i-Pr2NEt (0.025 mL, 0.14 mmol). A solution of 2-adamantyl isocyanate (25 mg, 0.14 mmol) in CH2Cl2 (2 mL) was added with stirring. After stirring overnight the mixture was applied to a 10-mL ChemElut cartridge that had been prewetted with 5% aq HCl (6 mL). The cartridge was eluted with ether (20 mL). The eluate was evaporated to dryness and the residue was applied to a 2-g silica SPE cartridge. The cartridge was eluted sequentially with 0, 10, 25, 50, 75 and 100% EtOAc in hexanes (15 mL of each) to afford six fractions. Fractions 4 and 5 were pooled and concentrated to afford (R)-tert-butyl 1-(2-adamantylcarbamoyl)pyrrolidin-3-ylcarbamate (7.9 mg, 15%). LC-MS Method 1, tR=1.83 min, m/z=364; 1H NMR (CDCl3) 1.42 (s, 9H), 1.60-1.95 (15H), 2.17 (m, 1H), 3.21 (m, 1H), 3.46 (m, 2H), 3.61 (m, 1H), 3.96 (m, 1H), 4.22 (1H), 4.53 (d, 1H), 4.72 (1H)

Provenance & Evidence