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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 1706622Generated: October 26, 2026

Hydrochloric Acid → Rac.-3,4-Dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-acetonitrile

https://huagongshe.com/reaction/1706622

Reaction equation

Participants

RoleNameHCIDCharge
ReactantHydrochloric AcidHCID 313—
ReactantAcetonitrileHCID 6342—
ReactantEthyl AcetateHCID 8857—
ReactantPotassium HydroxideHCID 14797—
Reactant2H-1-Benzopyran-2,6-diol, 3,4-dihydro-2,5,7,8-tetramethyl-HCID 103737—
ProductRac.-3,4-Dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-acetonitrileHCID 20333800—

Reaction Steps

A mixture of 9.0 g (40.5 mmoles) of 2,6-dihydroxy-2,5,7,8-tetramethylchroman and 4.54 g (69 mmoles) of 85% KOH in 61 ml of acetonitrile was rapidly stirred and refluxed for 4 hr. The dark-colored mixture, which consisted of two phases, was cooled in an ice bath and treated dropwise, with stirring, with 25 ml of 3 N aqueous HCl whereupon the reaction mixture became lighter in color. This mixture was poured into 1 N aqueous HCl and worked-up with ethyl acetate in the usual manner (the organic extracts were additionally washed with saturated aqueous NaHCO3 solution) affording 14.8 g of rac.-3,4-dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-acetonitrile as a red solid.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS04208333
Source datasetuspto-grants-1980_06
ORD IDord-ba64621d680f4568b1bc2ecd7270436a
Source noteuspto-grants-1980_06