4-Bromobenzyl bromide → 5-(4-Bromobenzyl)-3-isobutoxycyclopent-2-enone

Temperature

-78 °C

3-Isobutoxycyclopent-2-enone (3, 0.130 g, 0.84 mmol) in anhydrous tetrahydrofuran (2.0 mL) was cooled to −78° C. and a freshly prepared 1M solution of lithium diisopropylamide (1.0 mL, 1.0 mmol) was added dropwise. The mixture was stirred at −78° C. for 45 min and a solution of 1-bromo-4-(bromomethyl)benzene (0.210 g, 0.84 mmol) in anhydrous tetrahydrofuran (3.0 mL) was added dropwise. The resulting mixture was stirred for 1 h allowing the temperature to rise to rt. The reaction was quenched with a saturated aqueous solution of ammonium chloride (3.0 mL). The aqueous phase was extracted with ethyl acetate (2×10 mL) and combined organic layers were washed with brine, dried over magnesium sulfate, filtered and concentrated in vacuo. Purification by silica gel column chromatography using a gradient of ethyl acetate in hexanes as eluant provided 5 as a white solid (40% yield).

1. stirringThe resulting mixture was stirred for 1 h
2. customto rise to rt
3. customThe reaction was quenched with a saturated aqueous solution of ammonium chloride (3.0 mL)
4. extractionThe aqueous phase was extracted with ethyl acetate (2×10 mL)
5. washwere washed with brine
6. dry with materialdried over magnesium sulfate
7. filtrationfiltered
8. concentrationconcentrated in vacuo
9. customPurification by silica gel column chromatography

ORD record

ord-4c27ae70437a4d4a937e222e6ed48690

Source dataset

uspto-grants-2013_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08530520B2