Potassium Fluoride → 2,2,4-Trimethyl-6-thiophen-3-yl-1,2-dihydroquinoline

To a dry 50 mL round bottom flask charged with a mixture of trifluoromethanesulfonic acid 2,2,4-trimethyl-1,2-dihydroquinolin-6-yl ester (0.50 g, 1.56 mmol), Pd(OAc)2 (0.035 g, 0.156 mmol), di-tert-butylbiphenylphosphine (DTBBPP) (0.093 g, 0.312 mmol), and KF (0.27 g, 4.67 mmol) suspended in THF (5 mL), was added 3-thiopheneboronic acid (0.30 g, 2.33 mmol). The flask was evacuated and flushed three times with argon and the reaction mixture was allowed to stir at room temperature for 2 days. The reaction mixture was filtered through diatomaceous earth and diluted with EtOAc (50 mL). The mixture was sequentially washed with water (10 mL), NaOH (1.0 M, 10 mL), and brine (10 mL). The organic phase was dried over sodium sulfate (Na2SO4), filtered, and concentrated in vacuo. The crude residue was purified by chromatography (silica gel, 30% dichloromethane in hexanes) to give 2,2,4-trimethyl-6-thiophen-3-yl-1,2-dihydroquinoline (0.128 g, 32%).

1. customThe flask was evacuated
2. customflushed three times with argon
3. filtrationThe reaction mixture was filtered through diatomaceous earth
4. additiondiluted with EtOAc (50 mL)
5. washThe mixture was sequentially washed with water (10 mL), NaOH (1.0 M, 10 mL), and brine (10 mL)
6. dry with materialThe organic phase was dried over sodium sulfate (Na2SO4)
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customThe crude residue was purified by chromatography (silica gel, 30% dichloromethane in hexanes)

ORD record

ord-a5b4cd99bc954d7a8d729932cf755d5b

Source dataset

uspto-grants-2005_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06858627B2