6-bromospiro[benzo[b][1,4]oxazine-2,1'-cyclopropan]-3(4H)-one → 6-Bromo-3,4-dihydrospiro[benzo[b][1,4]oxazine-2,1'-cyclopropane]

Temperatur

75 °C

A solution of 1 M Borane-THF complex in THF (2.6 mL) was added to a solution of 6-bromospiro[benzo[b][1,4]oxazine-2,1′-cyclopropan]-3(4H)-one 7.21 (135 mg, 0.53 mmol) in THF (1.5 mL) at room temperature. Mixture was heated at 75° C. for 16 hours. After cooling to room temperature, reaction mixture was quenched with methanol, diluted with ethyl acetate, and washed with sat. NaHCO3 (aq). Layers were separated and aqueous was extracted with ethyl acetate. Combined organics were washed with brine, dried (Na2SO4), filtered, and concentrated under reduced pressure to yield 6-bromo-3,4-dihydrospiro[benzo[b][1,4]oxazine-2,1′-cyclopropane] 7.23 (127 mg), which was used without further purification. LCMS-ESI+ (m/z): [M+H]+ calcd for C10H11BrNO: 239.99; found: 239.96.

1. temperatureAfter cooling to room temperature
2. customreaction mixture
3. customwas quenched with methanol
4. additiondiluted with ethyl acetate
5. washwashed with sat. NaHCO3 (aq)
6. customLayers were separated
7. extractionaqueous was extracted with ethyl acetate
8. washCombined organics were washed with brine
9. dry with materialdried (Na2SO4)
10. filtrationfiltered
11. concentrationconcentrated under reduced pressure

ORD-Eintrag

ord-0ac37b35e2cd4077b72872e65a426187

Quelldatensatz

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09376441B2