(7-bromo-9,9-dimethyl-9H-fluoren-2-yl)methanol synthesis

Yield:-

Reaction Conditions:

with sodium bis(2-methoxyethoxy)aluminium dihydride in toluene at 0 - 20; for 3 h;Inert atmosphere;

Steps:

7.I

In the stream of argon, 39.4g of intermediate i-1 and 130 mL of toluene were put in a 2000 mL-recovery flask, and the resulting solution was cooled to 0°C. To this reaction liquid, 43.7 mL of a toluene (70% toluene (3.6M)) solution (260 mL) of sodium bis(2-methoxyethoxy)aluminum hydride was added dropwise. The resulting mixture was heated to room temperature, and allowed to react at room temperature for 3 hours. The reaction solution was cooled to 0°C, and 3N hydrochloric acid was added dropwise. When the reaction solution became acidic, the solution was separated and extracted by adding ethyl acetate. An organic phase was washed with saturated saline, dried with sodium sulfate and concentrated to obtain solids. The resulting solids were purified with silica gel chromatography (hexane/ethyl acetate (4/1)), and solids obtained were dried under reduced pressure to obtain 37.9g of white solids. The white solids were identified as intermediate i-13 by FD-MS analysis.

References:

EP2423179,2012,A1 Location in patent:Page/Page column 55-56