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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 440687Generated: October 30, 2026

Water → 8-amino-3,4-dihydro-7-fluoro-2H-1-benzopyran

https://huagongshe.com/reaction/440687

Reaction equation

Participants

RoleNameHCIDCharge
ReactantWaterHCID 962—
ReactantTrifluoroacetic acidHCID 6422—
ReactantSodium BicarbonateHCID 516892—
Reactant1,1-dimethylethyl N-(3,4-dihydro-7-fluoro-2H-1-benzopyran-8-yl)carbamateHCID 22404771—
SolventDiethyl EtherHCID 3283—
Product8-amino-3,4-dihydro-7-fluoro-2H-1-benzopyranHCID 2240479596.2%

Reaction Steps

Trifluoroacetic acid, 50 mL, was stirred and cooled in an ice-water bath, and 6.1 grams (0.023 mole) of 1,1-dimethylethyl N-(3,4-dihydro-7-fluoro-2H-1-benzopyran-8-yl)carbamate was added portionwise. Upon completion of the addition, the reaction mixture was stirred for one hour, then stirred with water and diethyl ether and neutralized with solid sodium bicarbonate. The water layer was separated and extracted with diethyl ether. The extract was combined with the organic layer, and the combination was washed with water. The organic layer was dried with magnesium sulfate and filtered. The filtrate was concentrated under reduced pressure, yielding 3.7 grams of 8-amino-3,4-dihydro-7-fluoro-2H-1-benzopyran. The NMR spectrum was consistent with the proposed structure.

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS05521147
Source datasetuspto-grants-1996_05
ORD IDord-0fb692180f8340cc933309255eaaf267
Source noteuspto-grants-1996_05