Sodium Carbonate → 4-(4-methoxy-3-nitro-phenyl)-3,6-dihydro-2H-pyran

HRID 1582102Notes

Reaction equation

[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6](B2OC(C)(C)C(C)(C)O2)=[CH:5][C:4]=1[N+:18]([O-:20])=[O:19].[O:21]1[CH2:26][CH:25]=[C:24](OS(C(F)(F)F)(=O)=O)[CH2:23][CH2:22]1.C(=O)([O-])[O-].[Na+].[Na+]>C(O)C.C1(C)C=CC=CC=1.[CH-]1C=C(P(C2C=CC=CC=2)C2C=CC=CC=2)C=C1.[CH-]1C=C(P(C2C=CC=CC=2)C2C=CC=CC=2)C=C1.Cl[Pd]Cl.[Fe+2]>[CH3:1][O:2][C:3]1[CH:8]=[CH:7][C:6]([C:24]2[CH2:25][CH2:26][O:21][CH2:22][CH:23]=2)=[CH:5][C:4]=1[N+:18]([O-:20])=[O:19]

Participants

Conditions

Temperature: 80 °C

Procedure

To a stirred solution of 4.36 g (15.6 mmol) 2-(4-methoxy-3-nitro-phenyl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane and 3.30 g (14.2 mmol) trifluoromethanesulfonic acid 3,6-dihydro-2H-pyran-4-yl ester in 33 ml ethanol and 82 ml toluene was added 580 mg (0.71 mmol) dichloro(1,1′-bis(diphenylphosphino)ferrocene)palladium(II) dichloromethane adduct. The mixture was heated at 80° C. and 16.5 ml (33.0 mmol) 2 M aqueous sodium carbonate solution was added dropwise. The reaction mixture was stirred for 20 minutes at 80° C. and then cooled to room temperature, poured onto water, and extracted three times with ethyl acetate. The combined organic phases were dried over sodium sulfate and concentrated in vacuo. Flash chromatography (1/4 ethyl acetate/hexane) afforded 2.00 g (60%) 4-(4-methoxy-3-nitro-phenyl)-3,6-dihydro-2H-pyran as a light yellow solid. ES-MS m/e (%): 253 (M+NH4+, 100), 236 (M+H+, 24).

Workup

temperaturecooled to room temperature
additionpoured onto water
extractionextracted three times with ethyl acetate
dry with materialThe combined organic phases were dried over sodium sulfate
concentrationconcentrated in vacuo

Sources & evidence

ORD record: ord-41c1932897c54a7a83e9e1c131c88957
Source dataset: uspto-grants-2004_05
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US06734179B2

Reaction notes

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