Methyl iodide → 5-(Benzyloxy)-7-bromo-2-methylbenzo[d]thiazole

Temperature

-78 °C

A 1.0 M THF solution of LiHMDS (3.0 mL, 3.0 mmol) was diluted into THF (20 mL) under Ar, and the resulting solution was cooled to −78° C. 5-(benzyloxy)-7-bromobenzo[d]thiazole (4.03) (807 mg, 2.52 mmol) was added as a solution in THF (4 mL) over 2 min, washing with additional THF (3×2 mL). The resulting mixture was stirred 30 min, and MeI (0.47 mL, 7.6 mmol) was added in one portion. After stifling an additional 10 min, the mixture was removed from the cold bath and was allowed to warm to r.t. After 1.25 h at r.t., the reaction was diluted with saturated aqueous NH4Cl (50 mL), water (15 mL), and EtOAc (50 mL). The phases were separated, and the organic phase was dried over Na2SO4, filtered, and concentrated to afford a crude residue that was purified by silica gel chromatography (0-20% EtOAc in hexanes) to afford 5-(benzyloxy)-7-bromo-2-methylbenzo[d]thiazole 4.03D. LCMS-ESI+ (m/z): [M+H]+ calcd for C15H13BrNOS: 334.0. found: 334.0.

1. washwashing with additional THF (3×2 mL)
2. waitAfter stifling an additional 10 min
3. customthe mixture was removed from the cold bath
4. temperatureto warm to r.t
5. waitAfter 1.25 h at r.t.
6. additionthe reaction was diluted with saturated aqueous NH4Cl (50 mL), water (15 mL), and EtOAc (50 mL)
7. customThe phases were separated
8. dry with materialthe organic phase was dried over Na2SO4
9. filtrationfiltered
10. concentrationconcentrated
11. customto afford a crude residue that
12. customwas purified by silica gel chromatography (0-20% EtOAc in hexanes)

ORD record

ord-3eca1eda370d48b2be5d17826749fb5a

Source dataset

uspto-grants-2016_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09376441B2