Benzyl Bromide → HCID 20142724, compound

Participants

Reaction Conditions

Reaction Steps

Under dry N2, diisopropylamine (1.7 ml, 0.012 mol) was dissolved in tetrahydrofuran (20 ml) and cooled to -78° C. Butyl lithium (6.88 ml of 1.6 M in hexane, 0.011 mol) was added, and the mixture stirred at -20° C for 0.5 hour and then recooled to -78° C. 6-Bromo-3,4-dihydro-1(2H)-naphthalenone (2.25 g, 0.010 mol; J. Am. Chem. Soc. v. 102, p. 7920, 1980), dissolved in tetrahydrofuran (10 ml) was added, the mixture warmed to -20° C. over 0.5 hour and stirred at that temperature for 15 minutes. Finally benzyl bromide (1.3 ml, 0.011 mol) was added, the mixture warmed over 1 hour to ambient temperature, and stirred at that temperature for 16 hours. The reaction was quenched with two volumes of 10% HCl and extracted with 150 ml ether. The organic layer was washed with 100 ml saturated brine, dried (MgSO4), stripped in vacuo, and the residue chromatographed on silica gel using 1:1 hexane:CH2Cl2 as eluant, monitoring by tlc (1:2 hexane:CH2CL2). Recovered was 380 mg of bis-benzylated product (Rf 0.58), 750 mg of title product (Rf 0.50) and 1.1 g of starting material (Rf 0.28), suitable for recycling.

Provenance & Evidence