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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 437195Generated: October 25, 2026

Hydrochloric Acid → DH 990

https://huagongshe.com/reaction/437195

Reaction equation

Participants

RoleNameHCIDCharge
ReactantHydrochloric AcidHCID 313—
Reactant2-Bromohexanoic acidHCID 12013—
ReactantSodium HydroxideHCID 14798—
Reactant2,6-Di-tert-butyl-4-mercaptophenolHCID 70370—
SolventEthanolHCID 702—
SolventWaterHCID 962—
ProductDH 990HCID 40826—

Reaction Steps

A base solution (22 grams of NaOH in 41 milliliters (ml) of water) was added to a solution of 2,6-di-t-butyl-4-mercaptophenol (64.3 grams; 0.27 mole) in 540 ml. of absolute ethanol with stirring while cooling the reaction mixture under nitrogen. Following the base addition, a solution of 2-bromohexanoic acid (52.8 grams; 0.27 mole) in 27 ml. of ethanol was added and the resulting reaction mixture was stirred at room temperature for about 6 hours and left standing overnight. The reaction mixture was then diluted with about 400 ml. of water and acidified with cold 6N HCl. The yellow brown precipitate resulting from the acidification was obtained by filtration, washed with water and recrystallized from a methylene chloride-hexane mixture. As a result of these operations, the desired 2-((3,5-di-tert-butyl-4-hydroxyphenyl)thio)hexanoic acid compound was obtained as a white crystalline solid having a melting point of 140°-142° C. Analysis calculated for C20H32O3S: C, 68.15; H, 9.14; S, 9.10. Found: C, 68.14; H, 9.34; S, 8.86.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS04029812
Source datasetuspto-grants-1977_06
ORD IDord-9f9260db9e674878b9332e992fed83c2
Source noteuspto-grants-1977_06