Hydrochloric Acid → 3,3-Dimethyl-2,3-dihydro-1-benzofuran-5-ol

Temperature

90 °C

To a solution of [3-bromo-4-(2-methylallyloxy)phenyl]acetate (Intermediate 43, 190 mg, 0.67 mmol) in toluene (5 mL) azobisisobutyronitrile (0.13 g, 0.80 mmol) and tributylstannane (0.39 g, 1.33 mmol) were added and the reaction mixture was stirred for 2 hours at 90° C. Methanol (5 mL), water (3 mL) and sodium hydroxide 2M solution in water (0.67 ml, 1.33 mmol) were added and the reaction mixture was stirred for 1 hour at room temperature. A 2N aqueous solution of HCl was added while the pH was allowed to reach ˜3-4 and ethyl acetate (30 ml) was added. Two phases were separated and a 10% w/w solution of KF was added to the organic phase and the mixture was stirred for 1 hour at room temperature. The solid was filtered off and the solution was dried (Na2SO4), and evaporated. The residue was purified by flash chromatography (Biotage system) on silica gel using a SNAP 25 g as column and cyclohexane/ethyl acetate from 100:0 to 70:30 as eluent affording the title compound (95 mg) as white solid.

1. stirringthe reaction mixture was stirred for 1 hour at room temperature
2. additionwas added
3. customTwo phases were separated
4. additiona 10% w/w solution of KF was added to the organic phase
5. stirringthe mixture was stirred for 1 hour at room temperature
6. filtrationThe solid was filtered off
7. dry with materialthe solution was dried (Na2SO4)
8. customevaporated
9. customThe residue was purified by flash chromatography (Biotage system) on silica gel using a SNAP 25 g as column and cyclohexane/ethyl acetate from 100:0 to 70:30 as eluent

ORD record

ord-89b76bb34719454ebe991b6a4554eec8

Source dataset

uspto-grants-2015_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09193704B2