Allyl bromide → (2S)-1,1-Diphenyl-2-Allyloxy-Pent-4-en

Participants

Reaction Conditions

Reaction Steps

(2S)-1,1-diphenyl-pent-4-en-2-ol 25a (0.37 g, 1.57 mmol) was dissolved in dry DMF (2 ml) and was added to a suspension of NaH (60% in mineral oil, 0.13 g, 3.14 mmol) in dry DMF (20 ml) at 0° C. The reaction mixture was allowed to reach room temperature over a period of 1 h. The reaction mixture was cooled again to 0° C. employing an ice-bath, and neat allyl bromide (0.57 g, 4.71 mmol) was added via syringe. The reaction mixture was removed from the ice-bath and stirred overnight at room temperature. The reaction was cooled again to 0° C. and quenched by slowly adding H2O (20 ml). The resulting mixture was extracted with Et2O (3×50 ml), and the combined organic phases were washed in turn with H2O, brine, and then dried over anhydrous Na2SO4. Filtration followed by concentration gave crude product as light orange oil. Purification by chromatography (hexane/ethyl ether=10:1) gave 0.37 g (2S)-1,1-Diphenyl-2-Allyloxy-Pent-4-en (85%, [α]D=(+)19.7, c=1, MeOH).

Provenance & Evidence