5-bromo-2-methoxybenzaldehyde

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Tri-n-butyl-isopropenyltin (12.1 g, 36.6 mmol) dissolved in toluene (10 ml) was added to a mixture of 5-bromo-o-anisaldehyde (6.00 g, 27.9 mmol), tetrakis (triphenylphosphine)palladium (1.21 g, 1.05 mmol), and 2,6-t-butyl4-methylphenol (10 mg) in toluene (50 ml) under nitrogen at room temperature. This mixture was heated at reflux for 7 hr. Ether and aq. KF solution (80 ml) were added to the reaction mixture, and the resulting solution was stirred for 3 hr. Insoluble materials were removed by filtration through Celite. The filtrate was extracted with ether, and the organic phase was washed with 1N-NaHSO4 aq. NaHCO3 and brine. The extracts were dried over Na2SO4, and concentrated by evaporation. The residual oil was purified by chromatography (SiO2, 140 g, 5%-EtOAc/hexane) to afford 5-isopropenyl-o-anis-aldehyde, as a yellow oil (2.49 g, 51%). This mixture was heated at reflux for 7 hr Insoluble materials were removed by filtration through Celite The filtrate was extracted with ether the organic phase was washed with 1N-NaHSO4 aq. NaHCO3 and brine The extracts were dried over Na2SO4 concentrated by evaporation The residual oil was purified by chromatography (SiO2, 140 g, 5%-EtOAc/hexane)