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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1253290Generated: October 31, 2026

Formaldehyde → 1-Ethyl-4-hydroxy-1,3,4,9-tetrahydropyrano[3,4-b]indole-1-acetic Acid Methyl Ester

https://huagongshe.com/reaction/1253290

Reaction equation

Participants

RoleNameHCIDCharge
ReactantFormaldehydeHCID 712—
ReactantWaterHCID 962—
Reactant4-Amino-1-ethyl-1,3,4,9-tetrahydropyrano[3,4-b]indole-1-acetic acid methyl esterHCID 54323501—
SolventTetrahydrofuranHCID 8028—
Product1-Ethyl-4-hydroxy-1,3,4,9-tetrahydropyrano[3,4-b]indole-1-acetic Acid Methyl EsterHCID 1406472366.4%

Reaction Steps

To a solution of 4-amino-1-ethyl-1,3,4,9-tetrahydropyrano[3,4-b]indole-1-acetic acid methyl ester (6 g, 0.020 mol) in 50 mL THF was added 50 mL of H2O and paraformaldehyde (5 g) and the solution was heated at reflux for 2 hours under nitrogen. It was then cooled, concentrated in vacuo, and diluted with ethyl acetate. The ethyl acetate layer was washed with saturated sodium bicarbonate solution, brine, dried and concentrated in vacuo. The residue was purified by flash chromatography eluting with hexane to give a white solid (4 g, 66.4%) m.p. 86°-90° C.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS04748252
Source datasetuspto-grants-1988_05
ORD IDord-a6f2e00990214c2d94735a35b65b7d4c
Source noteuspto-grants-1988_05