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HuagongsheHuagongshe Chemistry Print Report · For research reference only
HRID 970502Generated: October 29, 2026

Hydrochloric Acid → 3-Quinolinecarboxylic acid,6-fluoro-1,2-dihydro-4-hydroxy-1-methyl-2-oxo-,ethyl ester

https://huagongshe.com/reaction/970502

Reaction equation

Participants

RoleNameHCIDCharge
ReactantHydrochloric AcidHCID 313—
ReactantDiethyl MalonateHCID 7761—
ReactantSodium hydrideHCID 24758—
Reactant6-Fluoro-1-methyl-2H-3,1-benzoxazine-2,4(1H)-dioneHCID 12713230—
ReactantHCID 178418361HCID 178418361—
SolventDimethylacetamideHCID 31374—
Product3-Quinolinecarboxylic acid,6-fluoro-1,2-dihydro-4-hydroxy-1-methyl-2-oxo-,ethyl esterHCID 6947725058.3%

Reaction Conditions

Temperature90 °C

Reaction Steps

Neat diethyl malonate (1.27 g, 8.4 mmol) was added slowly to a suspension of sodium hydride (60% in mineral oil, 372 mg, 9.3 mmol) in dimethylacetamide under N2 atmosphere. The mixture was stirred at room temperature until the evolution of hydrogen gas ceased, then the mixture was heated to 90° C. for 30 min. and cooled to room temperature. A solution of Compound 38 (1.8 g, 9.3 mmol) in dimethylacetamide was added slowly and the mixture heated overnight at 120° C. The mixture was cooled to room temperature, poured into ice water, and acidified by cold 10% HCl. The solids formed were filtered and washed several times by water to yield 1.3 g (53%) of white solids. M.P. 131° C. 1H NMR (DMSO-d6): δ 1.30 (t, J=6.9 Hz, 3H), 3.54 (s, 3H), 4.31 (q, J=6.9 Hz, 2H), 7.56 (dd, J=4.6, 9.3 Hz, 1H), 7.64 (dd, J=2.9, 9.1 Hz, 1H), 7.76 (dd, J=2.9, 9.3 Hz, 1H), 12.80 (s, 1H). EIMS m/z 266 (M+1), 288 (M+23).

Provenance & Evidence

DOI10.6084/m9.figshare.5104873.v1
Patent numberUS07312220B2
Source datasetuspto-grants-2007_12
ORD IDord-4e7051b024044beba42c13e8b9c27177
Source noteuspto-grants-2007_12