(R)-2-Methyl-CBS-oxazaborolidine → 5-((1R)-2-bromo-1-hydroxyethyl)-8-phenylmethoxy-1H-quinolin-2-one

Temperature

0 °C

A solution of [(R)-tetrahydro-1-methyl-3,3-diphenyl-1H,3H-pyrrolo[1,2-c] [1,3,2]-oxazaborole] (1M, 424 μL) in THF (2 ml) was added to borane dimethylsulfide complex (2M, 212.7 μl) in THF (15 ml) and stirred at 0° C. for 10 min. The reaction mixture was cooled to −10° C. and treated with a solution of 8-benzyloxy-5-bromoacetylcarbostyril (EP 147719A2) (791 mg) in THF (16 ml) over 20 min. Further borane dimethylsulfide complex (1.28 ml) was added over 4 h at 0° C. The reaction mixture was stirred for a further hour at 0° C. prior to quenching with methanol and 1N HCl(aq). The reaction mixture was partitioned between water and ethyl acetate. The organic phase was dried and concentrated in vacuo. The residue was triturated with hexane-ethyl acetate to afford the title compound (700 mg). Rf (EtOAc) 0.47

1. temperatureThe reaction mixture was cooled to −10° C.
2. additionFurther borane dimethylsulfide complex (1.28 ml) was added over 4 h at 0° C
3. stirringThe reaction mixture was stirred for a further hour at 0° C.
4. customto quenching with methanol and 1N HCl(aq)
5. customThe reaction mixture was partitioned between water and ethyl acetate
6. customThe organic phase was dried
7. concentrationconcentrated in vacuo
8. customThe residue was triturated with hexane-ethyl acetate

ORD record

ord-9c6e8be34950458987dcd749ec7d4912

Source dataset

uspto-grants-2008_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07402598B2