Allyl bromide → (+/-)-Dimethyl 2-allyl-1,2,3,4-tetrahydronaphthalene-2,6-dicarboxylate

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of (±)-dimethyl 1,2,3,4-tetrahydronaphthalene-2,6-dicarboxylate from Step A (10.0 g, 40.4 mmol) in THF (200 mL) at −70° C. was added sodium bis(trimethylsilyl)amide (1.0 M in THF, 45 mL, 45 mmol) dropwise, over 10 min, such that the reaction temperature was maintained below −65° C. during the addition. The mixture was stirred at −70° C. for a further 40 min, then allyl bromide (5.87 g, 48.5 mmol) was added dropwise over 3 min. Stirring was continued at −70° C. for 2 h, then the mixture was partitioned between H2O (300 mL) and EtOAc (300 mL). The aqueous phase was extracted further with EtOAc (2×300 mL), and the combined organic extracts were washed with brine (100 mL), dried over Na2SO4, filtered, and concentrated in vacuo. The crude product was purified by silica gel chromatography, eluting with a gradient of hexane:EtOAc—100:0 to 0:100, to give the title compound. MS: m/z=289 (M+1).

Provenance & Evidence