Methanesulfonic Acid → HCID 89558366, compound

Participants

Reaction Conditions

Reaction Steps

(1S,4S)-3-Oxo-2-oxa-5-aza-bicyclo[2.2.1]heptane-5-carboxylic acid tert-butyl ester (100.0 g, 469 mmol) was dissolved in ethyl acetate (970 mL) and methanesulfonic acid (43.5 mL, 659 mmol) was added at 45° C. The mixture was stirred for 16 h at 45° C. The suspension was cooled to room temperature, filtered, and the precipitate was washed with ethyl acetate (240 mL) and dried in vacuo to yield the title compound as a white crystalline solid (94.2 g, 96%). MS (EI, neg): m/z=113 [cation-H]+, 69 [cation-H—CO2]+, 68 [cation-H—HCO2]+. 1H NMR (DMSO-d6, 600 MHz): δ 2.12 (dd, J=1.2 Hz, 12.0 Hz, 1H), 2.33 (s, 3H), 2.59 (d, J=12.0 Hz, 1H), 3.33 and 3.50 (ABX, JAB=12.0 Hz, JAX=1.9 Hz, JBX=0 Hz, each 1H), 4.58 (s, 1H), 5.41 (s, 1H), 9.74 (br s, 2H).

Provenance & Evidence