3-溴苯甲醛缩乙二醛

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a stirred -78° C. solution of 3-bromobenzaldehyde diethyl acetal, prepared as in step 1, (1.0 g, 3.8 mmol) in THF (10 mL) was added n-butyllithium (1.7 mL, 4.25 mmol, 2.5M in hexanes). The cold reaction mixture was stirred 0.5 hours followed by the addition of a THF (5 mL) solution of iodine (1.09 g, 4.25 mmol). The ice bath was removed and the reaction allowed to warm to ambient temperature. Saturated NH4Cl was added and the mixture diluted with hexanes. The organic layer was washed with brine, dried (MgSO4) and concentrated under reduced pressure to give a residue which was purified by column chromatography on silica gel eluting with 5% ethyl acetate-hexanes to afford 1.0 g of 3-iodobenzaldehyde diethyl acetal. The cold reaction mixture The ice bath was removed Saturated NH4Cl was added the mixture diluted with hexanes The organic layer was washed with brine dried (MgSO4) concentrated under reduced pressure to give a residue which was purified by column chromatography on silica gel eluting with 5% ethyl acetate-hexanes

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a stirred -78° C. solution of 3-bromobenzaldehyde diethyl acetal, prepared as in step 1, (1.0 g, 3.8 mmol) in THF (10 mL) was added n-butyllithium (1.7 mL, 4.25 mmol, 2.5M in hexanes). The cold reaction mixture was stirred 0.5 hours followed by the addition of a THF (5 mL) solution of iodine (1.09 g, 4.25 mmol). The ice bath was removed and the reaction allowed to warm to ambient temperature. Saturated NH4Cl was added and the mixture diluted with hexanes. The organic layer was washed with brine, dried (MgSO4) and concentrated under reduced pressure to give a residue which was purified by column chromatography on silica gel eluting with 5% ethyl acetate-hexanes to afford 1.0 g of 3-iodobenzaldehyde diethyl acetal. The cold reaction mixture The ice bath was removed Saturated NH4Cl was added the mixture diluted with hexanes The organic layer was washed with brine dried (MgSO4) concentrated under reduced pressure to give a residue which was purified by column chromatography on silica gel eluting with 5% ethyl acetate-hexanes

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a stirred -78° C. solution of 3-bromobenzaldehyde diethyl acetal, prepared as in step 1, (1.0 g, 3.8 mmol) in THF (10 mL) was added n-butyllithium (1.7 mL, 4.25 mmol, 2.5M in hexanes). The cold reaction mixture was stirred 0.5 hours followed by the addition of a THF (5 mL) solution of iodine (1.09 g, 4.25 mmol). The ice bath was removed and the reaction allowed to warm to ambient temperature. Saturated NH4Cl was added and the mixture diluted with hexanes. The organic layer was washed with brine, dried (MgSO4) and concentrated under reduced pressure to give a residue which was purified by column chromatography on silica gel eluting with 5% ethyl acetate-hexanes to afford 1.0 g of 3-iodobenzaldehyde diethyl acetal. The cold reaction mixture The ice bath was removed Saturated NH4Cl was added the mixture diluted with hexanes The organic layer was washed with brine dried (MgSO4) concentrated under reduced pressure to give a residue which was purified by column chromatography on silica gel eluting with 5% ethyl acetate-hexanes

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a stirred solution of 3-bromobenzaldehyde (22.38 g, 121 mmol) in ethanol (150 mL) was added triethylorthoformate (27 g, 181 mmol) and concentrated HCl (0.5 mL). The mixture was heated to reflux for 3 hours and allowed to cool to ambient temperature. The reaction mixture was poured into ice/H2O and extracted thoroughly with hexanes. The combined organic extracts were washed with water and brine, dried (MgSO4) and concentrated in vacuo to give 34 g of 3-bromobenzaldehyde diethyl acetal as a colorless liquid. The mixture was heated to reflux for 3 hours extracted thoroughly with hexanes The combined organic extracts were washed with water and brine dried (MgSO4) concentrated in vacuo