Ammonium formate → HCID 18951360, compound

Participants

Reaction Steps

A mixture of 18 g (0.07 mmol) of ethyl 6,7-dihydro-9-hydroxypyrido[1,2-a]indole-8-carboxylate and 13.3 g of 0.21 mmol) of ammonium formate in 300 ml of ethanol is treated under a nitrogen atmosphere with 2.2 g of 10% palladium/charcoal and heated to reflux temperature for 4 hours. The resulting suspension is cooled to room temperature, filtered and the solid is washed with 50 ml of ethanol and twice with 50 ml of methylene chloride, each time. Then, the filtrate and the washings are evaporated and the residue is taken up in a mixture of ethyl acetate and water (5:4, total 450 ml). The organic phase is washed with 100 ml of sodium chloride solution, dried over anhydrous sodium sulfate and evaporated to dryness. In this manner, there are obtained 17.5 g (96%) of ethyl 6,7,8,9-tetrahydro-9-hydroxypyrido[1,2-a]indole-8-carboxylate as a beige solid, m.p. 116°-120° C.

Provenance & Evidence