Formaldehyde → 3-(4-Isopropylphenyl)-1',4,6,7-tetramethylspiro[benzofuran-2(3H), 4'-piperidine]-5-ol

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-(4-isopropylphenyl)-4,6,7-trimethylspiro[benzofuran-2(3H),4′-piperidine]-5-ol hydrochloride (2.80 g, 6.97 mmol), formic acid (30 mL) and 37% formalin (30 mL) was stirred for 15 hours at 100° C. The reaction mixture was cooled to room temperature, made basic with 8N sodium hydroxide solution, and extracted twice with ethyl acetate. The organic layers were combined, washed with an aqueous saturated sodium hydrogencarbonate, dried over magnesium sulfate, filtered, and concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (Chromatorex NH DM1020, Fuji Silysia Chemical LTD) (hexane/ethyl acetate=1/1) to obtain the title compound (2.05 g, yield 77%).

Provenance & Evidence