3-Bromobenzaldehyde → 1-Bromo-3-(2-methyl-1-propenyl)benzene

Temperature

-23 °C

To a suspension of iso-propyltriphenylphosphonium iodide in dry THF (150 mL) under nitrogen at −23° C. was added 2.5 M n-butyl lithium in hexanes (13.4 mL, 33.6 mmol). The resulting solution was stirred 0.5 hours at −23° C., the cooling bath was removed, and the reaction was stirred 0.5 hours at ambient temperature to give a dark red homogeneous solution which was cooled to −23° C. To the solution was added neat 3-bromobenzaldehyde (3.73 mL, 32 mmol). The cooling bath was removed, the reaction was stirred at ambient temperature for 1 hour, quenched by adding excess saturated ammonium chloride, and partitioned between ether and brine. The organic layer was washed with saturated aqueous Na2S2O5, brine, dried (Na2SO4), filtered, and concentrated under vacuum. Purification on silica gel with hexanes gave the title compound (5.34 g, 79%) as a colorless oil.

1. customthe cooling bath was removed
2. stirringthe reaction was stirred 0.5 hours at ambient temperature
3. customto give a dark red homogeneous solution which
4. temperaturewas cooled to −23° C
5. customThe cooling bath was removed
6. stirringthe reaction was stirred at ambient temperature for 1 hour
7. customquenched
8. additionby adding excess saturated ammonium chloride
9. custompartitioned between ether and brine
10. washThe organic layer was washed with saturated aqueous Na2S2O5, brine
11. dry with materialdried (Na2SO4)
12. filtrationfiltered
13. concentrationconcentrated under vacuum
14. customPurification on silica gel with hexanes

ORD record

ord-156aa50acb8d4a6ab5bdfdd0c739052b

Source dataset

uspto-grants-2001_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06284796B1