4-bromobutanal

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

Procedure: To a solution of 4-bromobutanal (prepared as described in J. Org. Chem., 1979, 44, 3230-3238: 450 mg, 2.98 mmol) in tetrahydrofuran (10 mL) at room temperature was added 1,3-propane diol (1.0 mL, 13.7 mmol) and p-toluenesulfonic acid monohydrate (50 mg, 0.26 mmol). The mixture was heated at reflux for 2 hours, cooled and suspended in a mixture of water and diethyl ether (200 mL of 1:1). The two layers were separated and the organic layer was dried over magnesium sulfate, filtered, and then concentrated in vacuo to give the title compound as a clear oil. The mixture was heated at reflux for 2 hours cooled The two layers were separated the organic layer was dried over magnesium sulfate filtered concentrated in vacuo

Conditions: temp:-20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Add (4-cyanophenylmethyl)triphenylphosphonium bromide (27.25 g) to dry THF (65 ml) and cool to -20° C. under an argon atmosphere. With stirring, dropwise add 65 ml of a solution of 1 molar lithium bis(trimethylsilyl)amide in THF, maintaining the temperature at -20° C. Stir for 30 minutes at -20° C.; then for 30 minutes at 0° C. Cool to -20° C. and add freshly distilled 4-bromobutanal (10.50 g) dropwise with stirring. Stir at -20° C. for 1 hour, then at room temperature for 16 hours. Remove the solid material by filtration and wash with THF. Vacuum evaporate the solvent from the filtrate and purify the resultant residue by chromatography on silica gel, eluting with CH2Cl2 :hexane(4:1). Combine the desired fractions and vacuum evaporate the solvent to obtain the title compound. Stir for 30 minutes at -20° C. Cool to -20° C. with stirring Stir at -20° C. for 1 hour at room temperature for 16 hours Remove the solid material by filtration wash with THF Vacuum evaporate the solvent from the filtrate purify the resultant residue by chromatography on silica gel eluting with CH2Cl2 :hexane(4:1) Combine the desired fractions and vacuum evaporate the solvent

Conditions: temp:-20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Add (4-cyanophenylmethyl)triphenylphosphonium bromide (27.25 g) to dry THF (65 ml) and cool to -20° C. under an argon atmosphere. With stirring, dropwise add 65 ml of a solution of 1 molar lithium bis(trimethylsilyl)amide in THF, maintaining the temperature at -20° C. Stir for 30 minutes at -20° C.; then for 30 minutes at 0° C. Cool to -20° C. and add freshly distilled 4-bromobutanal (10.50 g) dropwise with stirring. Stir at -20° C. for 1 hour, then at room temperature for 16 hours. Remove the solid material by filtration and wash with THF. Vacuum evaporate the solvent from the filtrate and purify the resultant residue by chromatography on silica gel, eluting with CH2Cl2 :hexane(4:1). Combine the desired fractions and vacuum evaporate the solvent to obtain the title compound. Stir for 30 minutes at -20° C. Cool to -20° C. with stirring Stir at -20° C. for 1 hour at room temperature for 16 hours Remove the solid material by filtration wash with THF Vacuum evaporate the solvent from the filtrate purify the resultant residue by chromatography on silica gel eluting with CH2Cl2 :hexane(4:1) Combine the desired fractions and vacuum evaporate the solvent

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

Procedure: To a solution of 4-bromobutanal (prepared as described in J. Org. Chem., 1979, 44, 3230-3238: 450 mg, 2.98 mmol) in tetrahydrofuran (10 mL) at room temperature was added 1,3-propane diol (1.0 mL, 13.7 mmol) and p-toluenesulfonic acid monohydrate (50 mg, 0.26 mmol). The mixture was heated at reflux for 2 hours, cooled and suspended in a mixture of water and diethyl ether (200 mL of 1:1). The two layers were separated and the organic layer was dried over magnesium sulfate, filtered, and then concentrated in vacuo to give the title compound as a clear oil. The mixture was heated at reflux for 2 hours cooled The two layers were separated the organic layer was dried over magnesium sulfate filtered concentrated in vacuo

Conditions: temp:-20.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Add (4-cyanophenylmethyl)triphenylphosphonium bromide (27.25 g) to dry THF (65 ml) and cool to -20° C. under an argon atmosphere. With stirring, dropwise add 65 ml of a solution of 1 molar lithium bis(trimethylsilyl)amide in THF, maintaining the temperature at -20° C. Stir for 30 minutes at -20° C.; then for 30 minutes at 0° C. Cool to -20° C. and add freshly distilled 4-bromobutanal (10.50 g) dropwise with stirring. Stir at -20° C. for 1 hour, then at room temperature for 16 hours. Remove the solid material by filtration and wash with THF. Vacuum evaporate the solvent from the filtrate and purify the resultant residue by chromatography on silica gel, eluting with CH2Cl2 :hexane(4:1). Combine the desired fractions and vacuum evaporate the solvent to obtain the title compound. Stir for 30 minutes at -20° C. Cool to -20° C. with stirring Stir at -20° C. for 1 hour at room temperature for 16 hours Remove the solid material by filtration wash with THF Vacuum evaporate the solvent from the filtrate purify the resultant residue by chromatography on silica gel eluting with CH2Cl2 :hexane(4:1) Combine the desired fractions and vacuum evaporate the solvent