Sodium Sulfite → 6-Benzothiazolecarboxaldehyde, 2-(methylthio)-

Temperature

0 °C

To a stirred mixture of (2-(methylthio)benzo[d]thiazol-6-yl)methanol (958 mg, 4.5 mmol) from Step 3 of Example 36 in CH2Cl2 (20 mL) at 0° C. under argon was added Dess-Martin periodinane (2.1 g, 5.0 mmol) in small portions. After the mixture was stirred for 1 hr at 0° C., it was diluted with CH2Cl2 (100 mL) followed by the addition of a 1:1 mixture of saturated aq Na2SO3 and saturated aq NaHCO3 (40 mL). The mixture was stirred for 10 min. The layers were separated and the CH2Cl2 layer was sequentially washed with saturated aq NaHCO3 (50 mL) and brine (50 mL). The organic layer was separated and dried over Na2SO4, filtered, and concentrated under reduced pressure to yield 2-(methylthio)benzo[d]thiazole-6-carbaldehyde (937 mg, 99%) as an off white solid which did not require further purification. 1H NMR (300 MHz, DMSO-d6) δ 10.06 (s, 1H), 8.62 (s, 1H), 7.99 (s, 2H), 2.84 (s, 3H); LCMS (ESI) m/z 210 (M+H)+.

1. stirringThe mixture was stirred for 10 min
2. customThe layers were separated
3. washthe CH2Cl2 layer was sequentially washed with saturated aq NaHCO3 (50 mL) and brine (50 mL)
4. customThe organic layer was separated
5. dry with materialdried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure

ORD record

ord-e1ce667838a742129a333fe07b1e8209

Source dataset

uspto-grants-2015_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08952058B2