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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 2206972Generated: October 29, 2026

L-Tryptophan → Methyl tryptophanate hydrochloride

https://huagongshe.com/reaction/2206972

Reaction equation

Participants

RoleNameHCIDCharge
ReactantL-TryptophanHCID 6305—
ReactantNinhydrinHCID 10236—
ReactantSodium HydroxideHCID 14798—
ReactantThionyl ChlorideHCID 24386—
SolventEthanolHCID 702—
SolventMethanolHCID 887—
ProductMethyl tryptophanate hydrochlorideHCID 2734891100%

Reaction Conditions

Temperature66 °C

Reaction Steps

Under ice bath, 100 ml round-bottom flask was added with 60 ml of methanol, and then slowly added with 4 ml of SOCl2 through constant pressure dropping funnel (with a drying tube on the top), and NaOH solution was used to absorb exhaust. After stirring for 1 h, 8 mmol of L-tryptophan was added and stirred at room temperature for 30 min, and then refluxed at 66° C. for 6 h. The reaction was tracked by TLC until the raw material disappears, with a solution of 2% ninhydrin in ethanol as chromogenic reagent. The solvent was evaporated out to obtain L-tryptophan methyl ester hydrochloride. Yield: 100%.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS09376382B2
Source datasetuspto-grants-2016_06
ORD IDord-f95ecde588c44ac3bc9a4fa567c67daf
Source noteuspto-grants-2016_06