Diethyl Ether → 6-Bromo-1-cyclopropyl-4,4-dimethyl-1,2,3,4-tetrahydroquinoline

Participants

Reaction Conditions

Reaction Steps

A stirred, cooled (0° C.) solution of 6-bromo-4,4-dimethyl-1,2,3,4-tetrahydro-quinoline-1-carbaldehyde (Intermediate 50, 21.8, 6.7 mmol) in anhydrous tetrahydrofuran (20 mL) under argon was treated with titanium tetra-iso-propoxide (2.15 mL, 7.39 mmol) followed by 3M solution of ethyl magnesium bromide in diethyl ether (5.6 mL, 16.8 mmol) and the reaction mixture was then heated at 50° C. overnight. It was then cooled in an ice-bath, quenched with saturated aqueous ammonium chloride solution and extracted with diethyl ether (×2). The combined organic phase was dried over anhydrous sodium sulfate, filtered over celite and evaporated in vacuo to residue which was subjected to flash column chromatography over silica gel (230-400 mesh) using 5% ethyl acetate in hexane as the eluent to afford the title compound as an oil (1.2 g, 64%).

Provenance & Evidence