tert-Butanol → HCID 69837016, compound

Temperature

0 °C

2-Methyl-2-propanol (120 mL), H2O (120 mL), and AD-mix-β (13.3 g) were combined together and cooled to 0° C. Concurrently, 6-chloro-8-difluoromethoxy-4-methylenethiochromane (2.65 g, 10.1 mmol; from step (iv) above) was cooled to −5° C. in an ice/MeOH bath. Once sufficiently cooled, the AD-mix-β solution was added and stirred at <0° C. for 2 h, then at room temperature for 4 h. The reaction was quenched with solid sodium sulfite (ca. 5.0 g) resulting in a clear solution which was then partitioned between EtOAc/H2O (1:1, 300 mL) and further extracted with EtOAc (100 mL). The organic extracts were combined and washed with 5 M H2SO4 (75 mL), saturated NaHCO3 (150 mL), and brine (150 mL), dried (Na2SO4), filtered, and concentrated in vacuo to afford 2.99 g (ca. 100%) of the sub-title compound as a yellow solid which was used without further purification. 1H NMR (300 MHz, CD3OD) δ 7.55 (s, 1H), 7.08 (s, 1H), 6.78 (t, J=75 Hz, 1H), 3.70 (d, J=12 Hz, 1H), 3.50 (d, J=12 Hz, 1H), 2.97-3.20 (m, 2H), 2.46-2.55 (m, 1H), 1.91-2.02 (m, 1H).

1. temperatureOnce sufficiently cooled
2. waitat room temperature for 4 h
3. customThe reaction was quenched with solid sodium sulfite (ca. 5.0 g)
4. customresulting in a clear solution which
5. customwas then partitioned between EtOAc/H2O (1:1, 300 mL)
6. extractionfurther extracted with EtOAc (100 mL)
7. washwashed with 5 M H2SO4 (75 mL), saturated NaHCO3 (150 mL), and brine (150 mL)
8. dry with materialdried (Na2SO4)
9. filtrationfiltered
10. concentrationconcentrated in vacuo

ORD record

ord-6f2916da47c643b6a34f4ceb540c5aaf

Source dataset

uspto-grants-2004_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06716834B2