Potassium Carbonate → 1-methyl-5-(2-oxo-1,2-dihydrospiro [3,1-benzoxazine-4,1'-cyclobutan]-6-yl)-1H-pyrrole-2-carbonitrile

To a solution of 1-methyl-1H-pyrrole-2-carbonitrile (0.84 g, 7.1 mmol) and triisopropylborate (1.8 mL, 7.8 mmol) in THF (15 mL) at 0° C. was added lithium diisopropylamide (4.6 mL, 9.2 mmol). The reaction was allowed to warm to room temperature. Upon completion by TLC, the reaction was added dropwise to a 65° C. solution of 6-bromospiro[3,1-benzoxazine-4,1′-cyclobutan]-2(1H)-one (0.38 g, 1.4 mmol), potassium carbonate (0.58 g, 4.2 mmol) dissolved in (5 mL water), and tetrakistriphenylphosphine palladium (0) (0.081 g, 0.07 mmol) in tetrahydrofuran (10 mL). Upon completion by TLC of the reaction the reaction mixture was poured into a saturated solution of ammonium chloride (100 mL), extracted with ethyl acetate (50 mL), dried with magnesium sulfate, and purified on a silica gel column (40% ethyl acetate/hexane) to give 1-methyl-5-(2-oxo-1,2-dihydrospiro[3,1-benzoxazine-4,1′-cyclobutan]-6-yl)-1H-pyrrole-2-carbonitrile (0.33 g, 79%) as a light red solid. 1H NMR (DMSO-d6): δ 10.41 (s, 1H), 7.58 (d, 1H, J=2 Hz), 7.43 (dd, 1H, J=8.2, 1.8 Hz), 7.04 (d, 1H, J=4.0 Hz), 6.39 (d, 1H, J=8.2 Hz), 6.39 (d, 1H, J=4.0 Hz), 3.73 (s, 3H), 2.55-2.49 (m, 2H), 2.05-1.90 (m, 2H), 1.88-1.83 (m, 2H). MS (ESI) m/z 294 ([M+H]+); MS (ESI) m/z 292 ([M−H]−). High resolution mass spectrometry (HRMS): calcd for C17H15N3O2, 293.1164; found (ESI_FT), 294.12311.

1. customUpon completion by TLC of the reaction the reaction mixture
2. extractionextracted with ethyl acetate (50 mL)
3. dry with materialdried with magnesium sulfate
4. custompurified on a silica gel column (40% ethyl acetate/hexane)

ORD-Eintrag

ord-28a12cc7ef4f4d18b0c593656d240a26

Quelldatensatz

uspto-grants-2007_09

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US07268149B2