Hydrochloric Acid → HCID 67462319, compound

Participants

Reaction Conditions

Reaction Steps

To tert-butyl 3-(diethoxymethyl)-4-oxo-spiro[chromane-2,4′-piperidine]-1′-carboxylate (33.0 g, 78.7 mmol) in toluene (73.33 mL) was added hydrochloric acid (68.8 mL of 4.0 M in dioxane, 275 mmol). The reaction mixture was heated at 60° C. for 15 min. Most of the solvent was removed under vacuum, and the tan slurry was filtered using a medium frit. The solids were washed with 500 mL of toluene. The solids were dried to give (Z)-3-(ethoxymethylene)spiro[chroman-2,4′-piperidin]-4-one hydrochloride (15.4 g, 63%). ESI-MS m/z calc. 273.1, found 274.3 (M+1)+; Retention time: 0.85 minutes (3 min run).

Provenance & Evidence