methyl 5-formyl-2-phenylmethoxybenzoate

Conditions: temp:-70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred suspension of methyltriphenylphosphonium bromide (4.1 g) in tetrahydrofuran (40 ml) was added 1.56M n-butyl lithium solution in hexane (7.2 ml) at room temperature, and the mixture was stirred for 1 hour. After the reaction mixture was cooled to −70° C., a solution of methyl 2-benzyloxy-5-formylbenzoate (2.82 g) in tetrahydrofuran (40 ml) was added, and the resulting mixture was stirred for 15 hours with gradually warming up to room temperature. To the reaction mixture was added water, and the resulting mixture was extracted with ethyl acetate. The extract was washed with brine and dried over anhydrous magnesium sulfate. After the solvent was removed under reduced pressure, purification of the residue by flash column chromatography on silica gel (eluent: hexane/ethyl acetate=4/1) gave methyl 2-benzyloxy-5-vinylbenzoate (2.63 g). the resulting mixture was stirred for 15 hours with gradually warming up to room temperature the resulting mixture was extracted with ethyl acetate The extract was washed with brine dried over anhydrous magnesium sulfate After the solvent was removed under reduced pressure, purification of the residue by flash column chromatography on silica gel (eluent: hexane/ethyl acetate=4/1)

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

Procedure: 39.1 g of methyl 2-benzyloxy-5-formyl-benzoate was dissolved in 300 ml methanol. 60 ml trimethyl orthoformate and 2 g of p-toluenesulffonic acid were added thereto, followed by heating under reflux for 4 hours. After cooling to room temperature, 5 ml triethylamine was added thereto, and the mixture was evaporated. The residue was dissolved in ethyl acetate, successively washed with water and saturated aqueous sodium bicarbonate solution, dried over anhydrous magnesium sulfate and the solvent was evaporated, to give 39.08 g of methyl 2-(benzyloxy)-5-(dimethoxymethyl)benzoate. by heating under reflux for 4 hours the mixture was evaporated The residue was dissolved in ethyl acetate successively washed with water and saturated aqueous sodium bicarbonate solution dried over anhydrous magnesium sulfate the solvent was evaporated

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

Procedure: 39.1 g of 2-benzyloxy-5-formylbenzoic acid methyl ester was dissolved in 300 ml of methanol. 60 ml of trimethyl orthoformate and 2 g of p-tosylic acid were added thereto, and the solution was heated under refluxed for 4 hours. After the solution was cooled down to room temperature, 5 ml of triethylamine was added thereto, and the solution was evaporated. The residue was dissolved in ethyl acetate, and the solution was successively washed with water and saturated sodium bicarbonate water, and dried over anhydrous magnesium sulfate, and the solvent was evaporated, to give 39.08 g of 2-(benzyloxy)-5-(dimethoxymethyl)benzoic acid methyl ester. the solution was heated under refluxed for 4 hours the solution was evaporated The residue was dissolved in ethyl acetate the solution was successively washed with water and saturated sodium bicarbonate water dried over anhydrous magnesium sulfate the solvent was evaporated