Ethyl formate → HCID 66842302, compound

Participants

Reaction Conditions

Reaction Steps

9-(4-Chloro-benzenesulfonyl)-7-oxo-9-aza-bicyclo[3.3.1]nonane-3-carboxylic acid ethyl ester (6) (2.49 g, 6.45 mmol) was dissolved in THF/ethanol (14 mL, 1/1, v/v). Ethyl formate (5.19 mL, 64.53 mmol) was added followed by sodium ethoxide (6.2 mL of 21% solution in ethanol). The resulting mixture was heated to 60° C. for 30 minutes after which the solution was cooled to room temperature and quenched by the addition of saturated aqueous NH4Cl (10 mL). The resulting mixture was extracted with EtOAc (2×20 mL) and the combined organic phases were dried (Na2SO4); filtered and concentrated under vacuum to yield 2.51 g (94%) of 9-(4-chloro-benzenesulfonyl)-6-hydroxymethylene-7-oxo-9-aza-bicyclo[3.3.1]nonane-3-carboxylic acid ethyl ester (7) as a yellow oil. Retention time (min)=2.017, method [1], MS (ESI) 414.0 (M+H).

Provenance & Evidence