4-methoxycyclopentene

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

Procedure: 88% Formic acid (90 ml) and 30% hydrogen peroxide (3.17 ml) were added to 4-methoxy-1-cyclopentene thus obtained, and the mixture was stirred overnight at room temperature. The reaction mixture was concentrated under reduced pressure, and a 35% aqueous solution of sodium hydroxide was added to the residue to alkalify the reaction mixture, followed by stirring at 50° C. for 10 minutes. The reaction mixture was cooled to room temperature and extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate. The solvent was distilled off, and the residue was purified by column chromatography on silica gel (methanol:methylene chloride=1:19) to obtain the title compound (1.21 g). thus obtained The reaction mixture was concentrated under reduced pressure a 35% aqueous solution of sodium hydroxide was added to the residue by stirring at 50° C. for 10 minutes The reaction mixture was cooled to room temperature extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate The solvent was distilled off the residue was purified by column chromatography on silica gel (methanol:methylene chloride=1:19)

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

Procedure: 88% Formic acid (90 ml) and 30% hydrogen peroxide (3.17 ml) were added to 4-methoxy-1-cyclopentene thus obtained, and the mixture was stirred overnight at room temperature. The reaction mixture was concentrated under reduced pressure, and a 35% aqueous solution of sodium hydroxide was added to the residue to alkalify the reaction mixture, followed by stirring at 50° C. for 10 minutes. The reaction mixture was cooled to room temperature and extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate. The solvent was distilled off, and the residue was purified by column chromatography on silica gel (methanol:dichloromethane=5:95) to obtain the title compound (1.21 g) as a colorless oil. thus obtained The reaction mixture was concentrated under reduced pressure a 35% aqueous solution of sodium hydroxide was added to the residue by stirring at 50° C. for 10 minutes The reaction mixture was cooled to room temperature extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate The solvent was distilled off the residue was purified by column chromatography on silica gel (methanol:dichloromethane=5:95)

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

Procedure: 88% Formic acid (90 ml) and 30% hydrogen peroxide (3.17 ml) were added to 4-methoxy-1-cyclopentene thus obtained, and the mixture was stirred overnight at room temperature. The reaction mixture was concentrated under reduced pressure, and a 35% aqueous solution of sodium hydroxide was added to the residue to alkalify the reaction mixture, followed by stirring at 50° C. for 10 minutes. The reaction mixture was cooled to room temperature and extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate. The solvent was distilled off, and the residue was purified by column chromatography on silica gel (methanol:dichloromethane=5:95) to obtain the title compound (1.21 g) as a colorless oil. thus obtained The reaction mixture was concentrated under reduced pressure a 35% aqueous solution of sodium hydroxide was added to the residue by stirring at 50° C. for 10 minutes The reaction mixture was cooled to room temperature extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate The solvent was distilled off the residue was purified by column chromatography on silica gel (methanol:dichloromethane=5:95)

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

Procedure: 88% Formic acid (90 ml) and 30% hydrogen peroxide (3.17 ml) were added to 4-methoxy-1-cyclopentene thus obtained, and the mixture was stirred overnight at room temperature. The reaction mixture was concentrated under reduced pressure, and a 35% aqueous solution of sodium hydroxide was added to the residue to alkalify the reaction mixture, followed by stirring at 50° C. for 10 minutes. The reaction mixture was cooled to room temperature and extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate. The solvent was distilled off, and the residue was purified by column chromatography on silica gel (methanol:dichloromethane=5:95) to obtain the title compound (1.21 g) as a colorless oil. thus obtained The reaction mixture was concentrated under reduced pressure a 35% aqueous solution of sodium hydroxide was added to the residue by stirring at 50° C. for 10 minutes The reaction mixture was cooled to room temperature extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate The solvent was distilled off the residue was purified by column chromatography on silica gel (methanol:dichloromethane=5:95)

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

Procedure: To the thus-obtained 4-methoxy-1-cyclopentene were added 88% formic acid (90 mL) and 30% hydrogen peroxide (3.17 mL) at room temperature, and the mixture was stirred at room temperature overnight. The reaction mixture was concentrated under reduced pressure, and 35% aqueous sodium hydroxide was added to the residue, to thereby make the reaction mixture basic, followed by stirring at 50° C. for 10 minutes. The resultant mixture was cooled to room temperature, and was extracted with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate, and the solvent was distilled away. The residue was purified by silica gel column chromatography (methanol:methylene chloride=1:19), to thereby give the title compound (1.21 g). The reaction mixture was concentrated under reduced pressure, and 35% aqueous sodium hydroxide was added to the residue by stirring at 50° C. for 10 minutes The resultant mixture was cooled to room temperature was extracted with ethyl acetate The organic layer was dried over anhydrous magnesium sulfate the solvent was distilled away The residue was purified by silica gel column chromatography (methanol:methylene chloride=1:19)

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

Procedure: 88% Formic acid (90 ml) and 30% hydrogen peroxide (3.17 ml) were added to 4-methoxy-1-cyclopentene thus obtained, and the mixture was stirred overnight at room temperature. The reaction mixture was concentrated under reduced pressure, and a 35% aqueous solution of sodium hydroxide was added to the residue to alkalify the reaction mixture, followed by stirring at 50° C. for 10 minutes. The reaction mixture was cooled to room temperature and extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate. The solvent was distilled off, and the residue was purified by column chromatography on silica gel (methanol:methylene chloride=1:19) to obtain the title compound (1.21 g). thus obtained The reaction mixture was concentrated under reduced pressure a 35% aqueous solution of sodium hydroxide was added to the residue by stirring at 50° C. for 10 minutes The reaction mixture was cooled to room temperature extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate The solvent was distilled off the residue was purified by column chromatography on silica gel (methanol:methylene chloride=1:19)

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

Procedure: 88% Formic acid (90 ml) and 30% hydrogen peroxide (3.17 ml) were added to 4-methoxy-1-cyclopentene thus obtained, and the mixture was stirred overnight at room temperature. The reaction mixture was concentrated under reduced pressure, and a 35% aqueous solution of sodium hydroxide was added to the residue to alkalify the reaction mixture, followed by stirring at 50° C. for 10 minutes. The reaction mixture was cooled to room temperature and extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate. The solvent was distilled off, and the residue was purified by column chromatography on silica gel (methanol:methylene chloride=1:19) to obtain the title compound (1.21 g). thus obtained The reaction mixture was concentrated under reduced pressure a 35% aqueous solution of sodium hydroxide was added to the residue by stirring at 50° C. for 10 minutes The reaction mixture was cooled to room temperature extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate The solvent was distilled off the residue was purified by column chromatography on silica gel (methanol:methylene chloride=1:19)

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

Procedure: 88% Formic acid (90 ml) and 30% hydrogen peroxide (3.17 ml) were added to 4-methoxy-1-cyclopentene thus obtained, and the mixture was stirred overnight at room temperature. The reaction mixture was concentrated under reduced pressure, and a 35% aqueous solution of sodium hydroxide was added to the residue to alkalify the reaction mixture, followed by stirring at 50° C. for 10 minutes. The reaction mixture was cooled to room temperature and extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate. The solvent was distilled off, and the residue was purified by column chromatography on silica gel (methanol:dichloromethane=5:95) to obtain the title compound (1.21 g) as a colorless oil. thus obtained The reaction mixture was concentrated under reduced pressure a 35% aqueous solution of sodium hydroxide was added to the residue by stirring at 50° C. for 10 minutes The reaction mixture was cooled to room temperature extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate The solvent was distilled off the residue was purified by column chromatography on silica gel (methanol:dichloromethane=5:95)

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

Procedure: 88% Formic acid (90 ml) and 30% hydrogen peroxide (3.17 ml) were added to 4-methoxy-1-cyclopentene thus obtained, and the mixture was stirred overnight at room temperature. The reaction mixture was concentrated under reduced pressure, and a 35% aqueous solution of sodium hydroxide was added to the residue to alkalify the reaction mixture, followed by stirring at 50° C. for 10 minutes. The reaction mixture was cooled to room temperature and extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate. The solvent was distilled off, and the residue was purified by column chromatography on silica gel (methanol:dichloromethane=5:95) to obtain the title compound (1.21 g) as a colorless oil. thus obtained The reaction mixture was concentrated under reduced pressure a 35% aqueous solution of sodium hydroxide was added to the residue by stirring at 50° C. for 10 minutes The reaction mixture was cooled to room temperature extracted with ethyl acetate to dry the organic layer over anhydrous magnesium sulfate The solvent was distilled off the residue was purified by column chromatography on silica gel (methanol:dichloromethane=5:95)