Allyl bromide → 1-Allyl-cyclohexane-1,3-dicarboxylic acid diethyl ester

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Reaction Conditions

Reaction Steps

To a cooled solution (−78° C.) of N,N-diisopropylamine (272 mL, 1.94 mol) in anhydrous THF (1.4 L) was added n-BuLi (1.6 M in hexane, 1.21 L, 1.94 mol) over the period of one hour and 20 minutes. The mixture was stirred at 0° C. for one hour and again cooled down to −78° C. DMPU (834 mL, 6.92 mol) was added dropwise, followed by the addition of the solution of cyclohexane-1,3-dicarboxylic acid diethyl ester from step 1 (316 g, 1.38 mol) in THF (400 mL). The mixture was stirred at −78° C. for 2.5 hours, and then allyl bromide (132 mL, 1.52 mol) was added. The mixture was warmed up to rt slowly and stirred at rt overnight. The mixture was quenched with ice-cold aqueous HCl (1 N, 1 L), diluted with ethyl acetate (30 mL) and extracted. The organic layer was washed with water (4×1.5 L), brine, dried over Na2SO4 and concentrated under reduced pressure to afford 371 g of the title compound as a thick oil, which was used in the next step without further purification.

Provenance & Evidence