Phenylacetaldehyde → HCID 66932609, compound

Participants

Reaction Steps

A suspension of (E)-3-{4-oxo-spiro[chromane-2,4′-piperidine]-6-yl}-acrylic acid methyl ester (2.0 g, 5.9 mmol, Intermediate 1, hydrochloride salt) in 1 M K2CO3 solution (30 ml) was stirred for 10 minutes, then DCM (3×30 ml) was added to extract the corresponding free base. The organic phase was dried and concentrated to 50 ml, then phenylacetaldehyde (0.79 ml, 7.10 mmol) and sodium triacethoxyborohydride (1.88 g, 8.88 mmol) were subsequently added. The mixture was stirred for 3 h, washed with water, and the pH value was adjusted to 8 with aqueous ammonia. The product was extracted with DCM and the organic solution was dried and concentrated. The crude residue was purified by column chromatography (eluent: DCM/MeOH 99:1 to 97:3) to give (E)-3-{1′-(2-phenyl-ethyl)-4-oxo-spiro[chromane-2,4′-piperidine]-6-yl}-acrylic acid methyl ester (1.72 g) as a light yellow solid.

Provenance & Evidence