4-hydroxy-3-prop-2-enylbenzaldehyde

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: The starting 3-allyl 4-hydroxybenzaldehyde was prepared from 4-hydroxybenzaldehyde using the method described in Example 1 for the preparation of 4-acetamido-2-allylphenol.

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

Procedure: 1,3-Dibromopropane (15.76 ml) and potassium carbonate (4.69 g) were added to a solution of 3-allyl-4-hydroxybenzaldehyde (5 g) in acetone and the reaction mixture heated at reflux for 16 hours. The reaction mixture was cooled to ambient temperature and filtered. The filtrate was evaporated and the residue purified by flash column chromatography on silica gel (Merck Art No 9385) using a 10:90 (v/v) mixture of ethyl acetate/hexane as eluent to give 3-allyl-4-(3-bromopropoxy)benzaldehyde (4.86 g) as an oil which slowly solidified. NMR([CD3 ]2SO): 2.2-2.4(2H,m), 3.35-3.50(2H,m), 3.65-3.80(2H,t), 4.2-4.3(2H,t), 5.0-5.15(2H,m), 5.8-6.1(1H,m), 7.15-7.25(1H,d), 7.7(1H,d), 7.75-7.85(1H,q) and 9,85(1H,s). the reaction mixture heated at reflux for 16 hours filtered The filtrate was evaporated the residue purified by flash column chromatography on silica gel (Merck Art No 9385) a 10:90 (v/v) mixture of ethyl acetate/hexane as eluent

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 40.5 g (0.25 mol) of 3-allyl-4-hydroxy-benzaldehyde, 10.3 g of sodium acetate, 19.9 g of N-acetylglycine and 63.5 g of acetic anhydride are together heated for 30 minutes to 100° C. and then for 21/2 hours to the reflux temperature. The resulting solution is cooled to 0° C. and the crystals which have separated out are filtered off, washed with water, dried in a vacuum desiccator and finally recrystallised from carbon tetrachloride. 2-Methyl-4-(4-acetoxy-3-allyl-benzylidene)-5-(4H)-oxazolone of melting point 108°-109° C. is obtained. 2 hours the crystals which have separated out are filtered off washed with water dried in a vacuum desiccator finally recrystallised from carbon tetrachloride

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 40.5 g (0.25 mol) of 3-allyl-4-hydroxy-benzaldehyde, 10.3 g of sodium acetate, 19.9 g of N-acetylglycine and 63.5 g of acetic anhydride are together heated for 30 minutes to 100° C. and then for 21/2 hours to the reflux temperature. The resulting solution is cooled to 0° C. and the crystals which have separated out are filtered off, washed with water, dried in a vacuum desiccator and finally recrystallised from carbon tetrachloride. 2-Methyl-4-(4-acetoxy-3-allyl-benzylidene)-5-(4H)-oxazolone of melting point 108°-109° C. is obtained. 2 hours the crystals which have separated out are filtered off washed with water dried in a vacuum desiccator finally recrystallised from carbon tetrachloride

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

Procedure: Two equivalents of potassium carbonate are added slowly with stirring to a solution of 4-hydroxybenzaldehyde in acetone. A solution of allyl bromide (1.1 equivalent) in acetone is added and the mixture is refluxed for two hours, filtered to remove inorganic salts and volatiles stripped under reduced pressure. The resulting 4-allyloxybenzaldehyde is then heated for six hours at 220° C. to yield the rearrangement product, 3-allyl-4-hydroxybenzaldehyde. One equivalent of 3-allyl-4-hydroxybenzaldehyde is dissolved in acetone and two equivalents of potassium carbonate are added slowly with stirring followed by a solution of 1.1 equivalents of methyl iodide in acetone. This mixture is refluxed for several hours, filtered and stripped to yield 3-allyl-4-methoxybenzaldehyde. This mixture is refluxed for several hours filtered

Conditions: temp:220.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Two equivalents of potassium carbonate are added slowly with stirring to a solution of 4-hydroxybenzaldehyde in acetone. A solution of allyl bromide (1.1 equivalent) in acetone is added and the mixture is refluxed for two hours, filtered to remove inorganic salts and volatiles stripped under reduced pressure. The resulting 4-allyloxybenzaldehyde is then heated for six hours at 220° C. to yield the rearrangement product, 3-allyl-4-hydroxybenzaldehyde. One equivalent of 3-allyl-4-hydroxybenzaldehyde is dissolved in acetone and two equivalents of potassium carbonate are added slowly with stirring followed by a solution of 1.1 equivalents of methyl iodide in acetone. This mixture is refluxed for several hours, filtered and stripped to yield 3-allyl-4-methoxybenzaldehyde. the mixture is refluxed for two hours filtered to remove inorganic salts and volatiles

Conditions: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 40.5 g (0.25 mol) of 3-allyl-4-hydroxy-benzaldehyde, 10.3 g of sodium acetate, 19.9 g of N-acetylglycine and 63.5 g of acetic anhydride are together heated for 30 minutes to 100°C and then for 21/2 hours to the reflux temperature. The resulting solution is cooled to 0°C and the crystals which have separated out are filtered off, washed with water, dried in a vacuum desiccator and finally recrystallised from carbon tetrachloride. 2-Methyl-4-(4-acetoxy-3-allyl-benzylidene)-5(4H)-oxazolone of melting point 108°-109°C is obtained. 2 hours the crystals which have separated out are filtered off washed with water dried in a vacuum desiccator finally recrystallised from carbon tetrachloride