4-bromo-3,5-difluorobenzaldehyde

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

Conditions: temp:22.01; 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: 6.0 g (0.03 mol) of 2-(4'-propylcyclohexyl)propane-1,3-diol, 6.6 g (0.03 mol) of 4-bromo-3,5-difluorobenzaldehyde and 0.3 g of TsOH were dissolved in 60 cm3 of dichloromethane, and it was refluxed for 3 hours on a hot water bath while removing the water produced with a Dean-Stark trap. After washing the reactant on water, the dichloromethane was removed. The residue was recrystallized from a solvent mixture of acetone and methanol to obtain 7.3 g (0.018 mol) of 2-(4'-bromo-3',5'-difluorophenyl)-5-(4'-propylcyclohexyl)-1,3-dioxane(trans-cis form mixture). it was refluxed for 3 hours on a hot water bath while removing the water produced with a Dean-Stark trap After washing the reactant on water the dichloromethane was removed The residue was recrystallized from a solvent mixture of acetone and methanol

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

Procedure: 10.8 g (0.074 mol) of 2-pentylpropane-1,3-diol, 16.3 g of 4-bromo-3,5-difluorobenzaldehyde and 0.7 g of TsOH were dissolved in 74 cm3 of dichloromethane, and was refluxed for 3 hours on a hot water bath with a Dean-Stark trap applied to remove the water formed. The reactant was washed in water, the dichloromethane was removed, and the residue was recrystallized from a mixture of acetone and methanol to obtain 9.1 g (0.026 mol) of 2-(4'-bromo-3',5'-difluorophenyl)-5-pentyl-1,3-dioxane. was refluxed for 3 hours on a hot water bath with a Dean-Stark trap to remove the water formed The reactant was washed in water the dichloromethane was removed the residue was recrystallized from a mixture of acetone and methanol

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

Procedure: 167 g (0.88 mol) of SnCl2 was added to 880 cm3 of diethyl ether, and dried HCl gas was absorbed to saturation at room temperature. 98 g (0.44 mol) of 4-bromo-3,5-difluorobenzonitrile was added all at once to this mixture, and after stirring for i hour, it was let stand overnight. The reactant was poured into 1,000 cm3 of water, and ether was distilled on a hot water bath at 50° C. The residue was extracted by adding chloroform, and after washing in water the chloroform was removed. The residue was distilled under reduced pressure (b. p. 96° C./73 mmHg) to obtain 88 g (0.40 mol) of 4-bromo-3,5-difluorobenzaldehyde. was absorbed to saturation at room temperature was distilled on a hot water bath at 50° C The residue was extracted by adding chloroform after washing in water the chloroform was removed The residue was distilled under reduced pressure (b. p. 96° C./73 mmHg)