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