Iodine → Benzyl 3-(hydroxymethylene)-4-oxo-spiro[chromane-2,4'-piperidine]-1'-carboxylate

Participants

Reaction Conditions

Reaction Steps

Iodine (2.88 g, 11.4 mmol) was slowly added to a solution of benzyl 3-(diethoxymethyl)-4-oxospiro[chroman-2,4′-piperidine]-1′-carboxylate (20.6 g, 45.4 mmol) in acetone (515 mL) and the mixture was stirred at 35° C. overnight. The reaction mixture was concentrated and the residue was purified by silica gel column chromatography (0-40% ethyl acetate in hexane) to afford benzyl 3-(hydroxymethylene)-4-oxospiro[chroman-2,4′-piperidine]-1′-carboxylate (15.2 g, 88%). ESI-MS m/z calc. 379.1, found 380.3 (M+1)+; Retention time: 2.00 minutes (3 min run).

Provenance & Evidence