3,3-Difluoro-cyclopentaneMethanol synthesis

Yield:-

Reaction Conditions:

with lithium aluminium tetrahydride in tetrahydrofuran;diethyl etherCooling with ice;Inert atmosphere;

Steps:

55 (3,3-Difluorocyclopentyl)methanol
6.4 ml of a 1M solution of lithium aluminum hydride in THF are initially charged in 40 ml of diethyl ether. With ice cooling, 1.12 g of ethyl 3,3-difluoro-cyclopentanecarboxylate dissolved in 10 ml of diethyl ether are added dropwise under argon. After one hour, the cooling bath is removed, and the reaction mixture is stirred for another three hours. The reaction mixture is then poured onto ice-cold saturated ammonium chloride solution and filtered off over a filtration aid. The filtrate is washed with saturated NaHCO₃ solution, dried over MgSO₄ and concentrated under reduced pressure. This gives 625 mg of (3,3-difluorocyclopentyl)methanol. C6H10F2O (136.14), GC-MS: 99.0 (M⁺-F-H2O).

References:

SANOFI-AVENTIS US2009/325942, 2009, A1 Location in patent:Page/Page column 55

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