Back
HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 52279Generated: October 28, 2026

Acetic Acid → (R)-3-(N-cyclopentylamino)-8-fluoro-5-methoxy-3,4-dihydro-2H-1-benzopyran

https://huagongshe.com/reaction/52279

Reaction equation

Participants

RoleNameHCIDCharge
ReactantAcetic AcidHCID 176—
ReactantCyclopentanoneHCID 8452—
ReactantSodium cyanoborohydrideHCID 5003444—
Reactant(R)-8-fluoro-5-methoxy-3-aminochromanHCID 22871215—
SolventMethanolHCID 887—
Product(R)-3-(N-cyclopentylamino)-8-fluoro-5-methoxy-3,4-dihydro-2H-1-benzopyranHCID 22871220—

Reaction Steps

To a solution of (R)-3-amino-8-fluoro-5-methoxy-3,4-dihydro-2H-1-benzopyran (2.5 g, 12 mmol), cyclopentanone (3.3 g, 36 mmol) and HOAc (0.7 g, 12 mmol) in methanol (25 mL ) was NaCNBH3 (2.5 g, 40 mmol) added in portions at room temperature. The solution was stirred at room temperature overnight to give a quantitative yield of the title compound. GC/MS (70 eV) M=265 (30%).

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS05616610
Source datasetuspto-grants-1997_04
ORD IDord-07d56c7705014e8b99ed6850acf83d07
Source noteuspto-grants-1997_04