cyclopentane-1,2-dione

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

Procedure: Stir a mixture of Cyclopentane-1,2-dione (2.00 g, 20.4 mmol), methyl 2-(2-oxopropylthio)acetate (3.31 g, 20.4 mmol) and potassium carbonate (5.63 g, 40.8 mmol) in DMF (40 mL) at 80° C. for 4 hours. Filter off the mixture and remove the solvent under vacuum. Purify the residue by a flash column on silica gel eluting with PE:EtOAc (8:1 to 6:1) to afford 3-Acetyl-5,6-dihydro-4H-cyclopenta[c]thiophene-1-carboxylic acid methyl ester as a pale yellow solid (206 mg, 4.5%). MS (m/z): 225 (M+1). Filter off the mixture remove the solvent under vacuum Purify the residue by a flash column on silica gel eluting with PE

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

Procedure: A solution of 73.5 g (0.75 mole) of 1,2-cyclopentanedione in 400 ml of ether was added to 1.5 moles of phenyl lithium in 1.2 liter of ether, and the mixture was stirred under N2 for one half hour. After careful addition of water, the ethereal layer was separated, dried over magnesium sulfate and the solvent evaporated. The residue was distilled under reduced pressure and gave 77.2 g of 2-hydroxy-2-phenylcyclopentanone, b.p. 122°-126° C. (1.5 mm), nD25 1.5551. The oxime was prepared by known procedures, m.p. 110°-112° C., and was reduced by hydrogenation over Raney nickel in 20% alcoholic ammonia. Removal of catalyst, evaporation of solvent and addition of HCl gave 2-hydroxy-2-phenylcyclopentylamine hydrochloride, m.p. 198°-199° C. the ethereal layer was separated dried over magnesium sulfate the solvent evaporated The residue was distilled under reduced pressure

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

Procedure: A solution of 73.5 g (0.75 mole) of 1,2-cyclopentanedione in 400 ml of ether was added to 1.5 moles of phenyl lithium in 1.2 liter of ether, and the mixture was stirred under N2 for one half hour. After careful addition of water, the ethereal layer was separated, dried over magnesium sulfate and the solvent evaporated. The residue was distilled under reduced pressure and gave 77.2 g of 2-hydroxy-2-phenylcyclopentanone, b.p. 122°-126° C. (1.5 mm), nD25 1.5551. The oxime was prepared by known procedures, m.p. 110°-112° C., and was reduced by hydrogenation over Raney nickel in 20% alcoholic ammonia. Removal of catalyst, evaporation of solvent and addition of HCl gave 2-hydroxy-2-phenylcyclopentylamine hydrochloride, m.p. 198°-199° C. the ethereal layer was separated dried over magnesium sulfate the solvent evaporated The residue was distilled under reduced pressure

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

Procedure: Stir a mixture of Cyclopentane-1,2-dione (2.00 g, 20.4 mmol), methyl 2-(2-oxopropylthio)acetate (3.31 g, 20.4 mmol) and potassium carbonate (5.63 g, 40.8 mmol) in DMF (40 mL) at 80° C. for 4 hours. Filter off the mixture and remove the solvent under vacuum. Purify the residue by a flash column on silica gel eluting with PE:EtOAc (8:1 to 6:1) to afford 3-Acetyl-5,6-dihydro-4H-cyclopenta[c]thiophene-1-carboxylic acid methyl ester as a pale yellow solid (206 mg, 4.5%). MS (m/z): 225 (M+1). Filter off the mixture remove the solvent under vacuum Purify the residue by a flash column on silica gel eluting with PE

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

Procedure: Stir a mixture of Cyclopentane-1,2-dione (2.00 g, 20.4 mmol), methyl 2-(2-oxopropylthio)acetate (3.31 g, 20.4 mmol) and potassium carbonate (5.63 g, 40.8 mmol) in DMF (40 mL) at 80° C. for 4 hours. Filter off the mixture and remove the solvent under vacuum. Purify the residue by a flash column on silica gel eluting with PE:EtOAc (8:1 to 6:1) to afford 3-Acetyl-5,6-dihydro-4H-cyclopenta[c]thiophene-1-carboxylic acid methyl ester as a pale yellow solid (206 mg, 4.5%). MS (m/z): 225 (M+1). Filter off the mixture remove the solvent under vacuum Purify the residue by a flash column on silica gel eluting with PE

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

Procedure: Stir a mixture of Cyclopentane-1,2-dione (2.00 g, 20.4 mmol), methyl 2-(2-oxopropylthio)acetate (3.31 g, 20.4 mmol) and potassium carbonate (5.63 g, 40.8 mmol) in DMF (40 mL) at 80° C. for 4 hours. Filter off the mixture and remove the solvent under vacuum. Purify the residue by a flash column on silica gel eluting with PE:EtOAc (8:1 to 6:1) to afford 3-Acetyl-5,6-dihydro-4H-cyclopenta[c]thiophene-1-carboxylic acid methyl ester as a pale yellow solid (206 mg, 4.5%). MS (m/z): 225 (M+1). Filter off the mixture remove the solvent under vacuum Purify the residue by a flash column on silica gel eluting with PE

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

Procedure: A solution of 73.5 g (0.75 mole) of 1,2-cyclopentanedione in 400 ml of ether was added to 1.5 moles of phenyl lithium in 1.2 liter of ether, and the mixture was stirred under N2 for one half hour. After careful addition of water, the ethereal layer was separated, dried over magnesium sulfate and the solvent evaporated. The residue was distilled under reduced pressure and gave 77.2 g of 2-hydroxy-2-phenylcyclopentanone, b.p. 122°-126° C. (1.5 mm), nD25 1.5551. The oxime was prepared by known procedures, m.p. 110°-112° C., and was reduced by hydrogenation over Raney nickel in 20% alcoholic ammonia. Removal of catalyst, evaporation of solvent and addition of HCl gave 2-hydroxy-2-phenylcyclopentylamine hydrochloride, m.p. 198°-199° C. the ethereal layer was separated dried over magnesium sulfate the solvent evaporated The residue was distilled under reduced pressure

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

Procedure: Stir a mixture of Cyclopentane-1,2-dione (2.00 g, 20.4 mmol), methyl 2-(2-oxopropylthio)acetate (3.31 g, 20.4 mmol) and potassium carbonate (5.63 g, 40.8 mmol) in DMF (40 mL) at 80° C. for 4 hours. Filter off the mixture and remove the solvent under vacuum. Purify the residue by a flash column on silica gel eluting with PE:EtOAc (8:1 to 6:1) to afford 3-Acetyl-5,6-dihydro-4H-cyclopenta[c]thiophene-1-carboxylic acid methyl ester as a pale yellow solid (206 mg, 4.5%). MS (m/z): 225 (M+1). Filter off the mixture remove the solvent under vacuum Purify the residue by a flash column on silica gel eluting with PE

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

Procedure: Stir a mixture of Cyclopentane-1,2-dione (2.00 g, 20.4 mmol), methyl 2-(2-oxopropylthio)acetate (3.31 g, 20.4 mmol) and potassium carbonate (5.63 g, 40.8 mmol) in DMF (40 mL) at 80° C. for 4 hours. Filter off the mixture and remove the solvent under vacuum. Purify the residue by a flash column on silica gel eluting with PE:EtOAc (8:1 to 6:1) to afford 3-Acetyl-5,6-dihydro-4H-cyclopenta[c]thiophene-1-carboxylic acid methyl ester as a pale yellow solid (206 mg, 4.5%). MS (m/z): 225 (M+1). Filter off the mixture remove the solvent under vacuum Purify the residue by a flash column on silica gel eluting with PE

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

Procedure: A solution of 73.5 g (0.75 mole) of 1,2-cyclopentanedione in 400 ml of ether was added to 1.5 moles of phenyl lithium in 1.2 liter of ether, and the mixture was stirred under N2 for one half hour. After careful addition of water, the ethereal layer was separated, dried over magnesium sulfate and the solvent evaporated. The residue was distilled under reduced pressure and gave 77.2 g of 2-hydroxy-2-phenylcyclopentanone, b.p. 122°-126° C. (1.5 mm), nD25 1.5551. The oxime was prepared by known procedures, m.p. 110°-112° C., and was reduced by hydrogenation over Raney nickel in 20% alcoholic ammonia. Removal of catalyst, evaporation of solvent and addition of HCl gave 2-hydroxy-2-phenylcyclopentylamine hydrochloride, m.p. 198°-199° C. the ethereal layer was separated dried over magnesium sulfate the solvent evaporated The residue was distilled under reduced pressure

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

Procedure: A solution of 73.5 g (0.75 mole) of 1,2-cyclopentanedione in 400 ml of ether was added to 1.5 moles of phenyl lithium in 1.2 liter of ether, and the mixture was stirred under N2 for one half hour. After careful addition of water, the ethereal layer was separated, dried over magnesium sulfate and the solvent evaporated. The residue was distilled under reduced pressure and gave 77.2 g of 2-hydroxy-2-phenylcyclopentanone, b.p. 122°-126° C. (1.5 mm), nD25 1.5551. The oxime was prepared by known procedures, m.p. 110°-112° C., and was reduced by hydrogenation over Raney nickel in 20% alcoholic ammonia. Removal of catalyst, evaporation of solvent and addition of HCl gave 2-hydroxy-2-phenylcyclopentylamine hydrochloride, m.p. 198°-199° C. the ethereal layer was separated dried over magnesium sulfate the solvent evaporated The residue was distilled under reduced pressure

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

Procedure: A solution of 73.5 g (0.75 mole) of 1,2-cyclopentanedione in 400 ml of ether was added to 1.5 moles of phenyl lithium in 1.2 liter of ether, and the mixture was stirred under N2 for one half hour. After careful addition of water, the ethereal layer was separated, dried over magnesium sulfate and the solvent evaporated. The residue was distilled under reduced pressure and gave 77.2 g of 2-hydroxy-2-phenylcyclopentanone, b.p. 122°-126° C. (1.5 mm), nD25 1.5551. The oxime was prepared by known procedures, m.p. 110°-112° C., and was reduced by hydrogenation over Raney nickel in 20% alcoholic ammonia. Removal of catalyst, evaporation of solvent and addition of HCl gave 2-hydroxy-2-phenylcyclopentylamine hydrochloride, m.p. 198°-199° C. the ethereal layer was separated dried over magnesium sulfate the solvent evaporated The residue was distilled under reduced pressure