Benzyl Bromide → HCID 19810539, compound

Temperature

-78 °C

δ-Valerolactone (7.14 g, 71.35 mmol) was slowly added to a flask containing freshly made LDA (80 mmol) in 200 ml of dry THF at -78° C. under N2. After stirring the solution for 40 min at -78° C., benzyl bromide (12.20 g, 71 mmol) was added. The bath was removed and the reaction was stirred at room temperature for 40 min. At the end, the crude mixture was poured to a slurry of AcOEt-Hexane and 0.5 N H2SO4. The organic layer was washed with brine, dried over MgSO4 and concentrated in vacuo. The crude product was then dissolved in 60 ml of MeOH and 10 ml of concentrated H2SO4. After stirring the solution at room temperature overnight, the acid was neutralized with aqueous NaHCO3. The crude product was extracted with AcOEt-Hexane and purified by column chromatography (silica gel, AcOEt-Hexane, 1:3) which gave 6.2 g (40% yield) of methyl 2-benzyl-5-hydroxy-pentanoate; 1H NMR (CDCl3, 300 MHz) δ: 7.30-7.10 (m,5H), 3.58 (s,3H,OCH3, 3.56 (t,J=6Hz,2H), 2.95 (dd,J=7,12Hz,1H), 2.75 (dd,J=6,12Hz,1H), 2.69 (m,1H), 2.15 (s,1H,-OH), and 1.70-1.50 (m,4H).

1. customThe bath was removed
2. stirringthe reaction was stirred at room temperature for 40 min
3. additionAt the end, the crude mixture was poured to a slurry of AcOEt-Hexane and 0.5 N H2SO4
4. washThe organic layer was washed with brine
5. dry with materialdried over MgSO4
6. concentrationconcentrated in vacuo
7. dissolutionThe crude product was then dissolved in 60 ml of MeOH
8. stirringAfter stirring the solution at room temperature overnight
9. extractionThe crude product was extracted with AcOEt-Hexane
10. custompurified by column chromatography (silica gel, AcOEt-Hexane, 1:3) which

ORD record

ord-4cd9546caf874000a1c6425fa5a6f9a7

Source dataset

uspto-grants-1992_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05164388