Dimethylformamide → 4-Methylene-3,4-dihydro-2H-pyrano[3,2-b]pyridine

HRID 899670

Reaktionsgleichung

Reaktionsgleichung von HRID 899670
CN(C=O)C.Br[C:7]1[C:12]([O:13][CH2:14][CH2:15][CH:16]=[CH2:17])=[CH:11][CH:10]=[CH:9][N:8]=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C([O-])(=O)C.[K+]>O.[Cl-].C([N+](CC)(CC)CC)C.CCOC(C)=O.[Cl-].[Na+].O.O.C([O-])(=O)C.[Pd+2].C([O-])(=O)C>[CH2:17]=[C:16]1[C:7]2=[N:8][CH:9]=[CH:10][CH:11]=[C:12]2[O:13][CH2:14][CH2:15]1

Komponenten

10

Edukt 4

HCID 6228DimethylformamideHCID 11776TriphenylphosphineHCID 517044Potassium AcetateHCID 220185632-Bromo-3-(but-3-en-1-yloxy)pyridine

Produkt 1

HCID 220186834-Methylene-3,4-dihydro-2H-pyrano[3,2-b]pyridineAusbeute 67,5 %

Reagenzien, Katalysatoren, Lösungsmittel 5

HCID 167845palladium(II) acetateKatalysatorHCID 16211205Tetraethylammonium chloride monohydrateKatalysatorHCID 962WaterLösungsmittelHCID 8857Ethyl AcetateLösungsmittelHCID 57417360Sodium chloride; waterLösungsmittel

Versuchsvorschrift

An anhydrous DMF solution (120 mL) of 2-bromo-3-but-3-enyloxy-pyridine (6.43 g, 28.2 mmol) in a round bottom schlenk flask was degassed with argon using the freeze/pump/thaw method. To this freshly degassed solution was added triphenylphosphine (2.66 g, 10.2 mmol), palladium acetate (696 mg, 3.10 mmol), potassium acetate (13.84 g, 141 mmol), and tetraethylammoniumchloride hydrate (9.35 g, 56.4 mmol). The resultant mixture was heated at 110 IC under argon for 18 hours. The reaction mixture was cooled to room temperature and diluted with EtOAc (300 mL), brine (120 mL) and H2O (60 mL). The organic phase was separated and washed with brine (3×120 mL) and dried over Na2SO4. Evaporation of the solvent and purification of the residue by flash chromatograph on silica gel (Hexanes/EtOAc, 95:5) afforded 4-methylene-3,4-dihydro-2H-pyrano[3,2-b]pyridine (2.8 g, 67%) as a white solid. 1H NMR (CDCl3) δ 2.79-2.86 (m, 2H), 4.25 (t, 2H, J=5.7 Hz), 5.08 (d, 1H, J=1.6 Hz), 6.19 (d, 1H, J=1.6 Hz), 7.08-7.17 (m, 2H), 8.20 (dd, 1H, J=4.7, 1.6 Hz).

Aufarbeitung

  1. customThe organic phase was separated
  2. washwashed with brine (3×120 mL)
  3. dry with materialdried over Na2SO4
  4. customEvaporation of the solvent and purification of the residue by flash chromatograph on silica gel (Hexanes/EtOAc, 95:5)

Quellen und Nachweise

ORD-Eintrag
ord-0af674c5adec4dbf8d026328e327800f
Quelldatensatz
uspto-grants-2008_04
Patentnummer
US07354932B2

Verknüpfte Notizen

Wird geladen…