N-(4-oxocyclohexyl)acetamide

Conditions: temp:0.00; pressure:0.00; stir:

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

Procedure: A solution of 15.5 g. of 4-acetamidocyclohexanone, 18 g. of 2,4-difluorophenylhydrazine hydrochloride and 10 g. of methanesulfonic acid in 200 ml. of absolute ethyl alcohol was heated under reflux for two hours, cooled, filtered, and the filtrate was evaporated to dryness under reduced pressure. The residual oil was triturated with water and the resulting solid was collected by filtration, triturated with ether, and recrystallized by dissolving in methanol, adding toluene, and evaporating the methanol to give 8.5 g. of 3-(acetamido)-6,8-difluoro-1,2,3,4-tetrahydrocarbazole, m.p. 179°-183° C. under reflux for two hours cooled filtered the filtrate was evaporated to dryness under reduced pressure The residual oil was triturated with water the resulting solid was collected by filtration triturated with ether recrystallized by dissolving in methanol adding toluene evaporating the methanol to give 8.5 g

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

Procedure: A solution of 7.8 g. of 4-acetamidocyclohexanone and 8.1 g. of 2-fluorophenylhydrazine hydrochloride in 75 ml. of absolute ethyl alcohol and 25 ml. of 5-N hydrogen chloride in absolute ethyl alcohol was heated under reflux for two hours, cooled, filtered, and the filtrate was evaporated to dryness. The residue was dissolved in chloroform and adsorbed on a column of aluminum oxide. Dilution with ether yielded first a small amount of side-product followed by the desired product which was recrystallized by dissolving in methyl alcohol, adding toluene, and evaporation of the methyl alcohol, to give 10.5 g. of 3-acetamido-8-fluoro-1,2,3,4-tetrahydrocarbazole, m.p. 202°-204° C. under reflux for two hours cooled filtered the filtrate was evaporated to dryness The residue was dissolved in chloroform Dilution with ether yielded first a small amount of side-product

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

Procedure: To a stirred suspension of sodium hydride (1.2 mmol) in THF was added triethyl phosphonoacetate (1.2 mmol) drop wise. The mixture was allowed to stir until it became colorless and a solution of N-(4-oxocyclohexyl)acetamide (1.0 mmol) in THF (1 mL) was added. The solution was allowed to stir at rt until the reaction was complete (by TLC). The solvent was removed under reduced pressure and the crude residue was filtered through a small plug of silica gel to afford the desired product, which was used directly in the next synthetic step. to stir at rt until the reaction The solvent was removed under reduced pressure the crude residue was filtered through a small plug of silica gel

Conditions: temp:0.00; pressure:0.00; stir:

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

Procedure: 3-Acetamido-8-fluoro-1,2,3,4-tetrahydrocarbazole -- A solution of 7.8 g. of 4-acetamidocyclohexanone and 8.1 g. of 2-fluorophenylhydrazine hydrochloride in 75 ml. of absolute ethyl alcohol and 25 ml. of 5-N hydrogen chloride in absolute ethyl alcohol was heated under reflux for two hours, cooled, filtered, and the filtrate was evaporated to dryness. The residue was dissolved in chloroform and adsorbed on a column of aluminum oxide. Dilution with ether yielded first a small amount of side-product followed by the desired product which was recrystallized by dissolving in methyl alcohol, adding toluene, and evaporation of the methyl alcohol, to give 10.5 g. of 3-acetamido-8-fluoro-1,2,3,4-tetrahydrocarbazole, m.p. 202°-204°C. under reflux for two hours cooled filtered the filtrate was evaporated to dryness The residue was dissolved in chloroform Dilution with ether yielded first a small amount of side-product

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

Procedure: 3-Acetamido-8-fluoro-1,2,3,4-tetrahydrocarbazole -- A solution of 7.8 g. of 4-acetamidocyclohexanone and 8.1 g. of 2-fluorophenylhydrazine hydrochloride in 75 ml. of absolute ethyl alcohol and 25 ml. of 5-N hydrogen chloride in absolute ethyl alcohol was heated under reflux for two hours, cooled, filtered, and the filtrate was evaporated to dryness. The residue was dissolved in chloroform and adsorbed on a column of aluminum oxide. Dilution with ether yielded first a small amount of side-product followed by the desired product which was recrystallized by dissolving in methyl alcohol, adding toluene, and evaporation of the methyl alcohol, to give 10.5 g. of 3-acetamido-8-fluoro-1,2,3,4-tetrahydrocarbazole, m.p. 202°-204°C. under reflux for two hours cooled filtered the filtrate was evaporated to dryness The residue was dissolved in chloroform Dilution with ether yielded first a small amount of side-product

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

Procedure: To a stirred suspension of sodium hydride (1.2 mmol) in THF was added triethyl phosphonoacetate (1.2 mmol) drop wise. The mixture was allowed to stir until it became colorless and a solution of N-(4-oxocyclohexyl)acetamide (1.0 mmol) in THF (1 mL) was added. The solution was allowed to stir at rt until the reaction was complete (by TLC). The solvent was removed under reduced pressure and the crude residue was filtered through a small plug of silica gel to afford the desired product, which was used directly in the next synthetic step. to stir at rt until the reaction The solvent was removed under reduced pressure the crude residue was filtered through a small plug of silica gel

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

Procedure: A solution of 7.8 g. of 4-acetamidocyclohexanone and 8.1 g. of 2-fluorophenylhydrazine hydrochloride in 75 ml. of absolute ethyl alcohol and 25 ml. of 5-N hydrogen chloride in absolute ethyl alcohol was heated under reflux for two hours, cooled, filtered, and the filtrate was evaporated to dryness. The residue was dissolved in chloroform and adsorbed on a column of aluminum oxide. Dilution with ether yielded first a small amount of side-product followed by the desired product which was recrystallized by dissolving in methyl alcohol, adding toluene and evaporation of the methyl alcohol, to give 10.5 g. of 3-acetamido-8-fluoro-1,2,3,4-tetrahydrocarbazole, m.p. 202°-204° C. under reflux for two hours cooled filtered the filtrate was evaporated to dryness The residue was dissolved in chloroform Dilution with ether yielded first a small amount of side-product

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

Procedure: To a solution of 6.7 g. of 4-acetamidocyclohexanone [prepared by the method of Fraser and Swingle, Can. J. Chem., 48, 2065 (1970)], in 150 ml. of anhydrous ethanol were added 25 ml. of ethyl orthoformate containing a few crystals of p-toluenesulfonic acid monohydrate. The reaction mixture was stirred at ambient temperature for about 16 hours, after which time the volatile constituents were removed by evaporation in vacuo. The residue comprising the diethylketal was dissolved in 200 ml. of toluene and the toluene was removed by distillation under a nitrogen atmosphere, until all of the diethylketal had been converted to the 1-ethoxycyclohexene derivative. The solution was cooled, washed with aqueous sodium bicarbonate and dried. Evaporation of the toluene yielded a residue comprising 4-acetamido-1-ethoxycyclohexene melting at 100°-102° C. after recrystallization from an ether-hexane solvent mixture; yield=6.2 g. after which time the volatile constituents were removed by evaporation in vacuo was dissolved in 200 ml of toluene and the toluene was removed by distillation under a nitrogen atmosphere The solution was cooled washed with aqueous sodium bicarbonate dried Evaporation of the toluene

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

Procedure: To a solution of 6.7 g. of 4-acetamidocyclohexanone [prepared by the method of Fraser and Swingle, Can. J. Chem., 48, 2065 (1970)], in 150 ml. of anhydrous ethanol were added 25 ml. of ethyl orthoformate containing a few crystals of p-toluenesulfonic acid monohydrate. The reaction mixture was stirred at ambient temperature for about 16 hours, after which time the volatile constituents were removed by evaporation in vacuo. The residue comprising the diethylketal was dissolved in 200 ml. of toluene and the toluene was removed by distillation under a nitrogen atmosphere, until all of the diethylketal had been converted to the 1-ethoxycyclohexene derivative. The solution was cooled, washed with aqueous sodium bicarbonate and dried. Evaporation of the toluene yielded a residue comprising 4-acetamido-1-ethoxycyclohexene melting at 100°-102° C. after recrystallization from an ether-hexane solvent mixture; yield=6.2 g. after which time the volatile constituents were removed by evaporation in vacuo was dissolved in 200 ml of toluene and the toluene was removed by distillation under a nitrogen atmosphere The solution was cooled washed with aqueous sodium bicarbonate dried Evaporation of the toluene

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

Procedure: A reaction mixture was prepared from 15.5 g. of 4-acetamidocyclohexanone [prepared by the procedure of Fraser and Swingle, Can. J. Chem., 48, 2065 (1970)], 80 g. of the dimethylacetal of dimethylformamide, 1.5 ml. of triethylamine and 500 ml. of benzene. The benzene was distilled therefrom over a 1.5 hour period until the volume was reduced to about 1/2 of the original volume. An additional 250 ml. of benzene were added. The reaction mixture was heated just below the boiling point of benzene for about 2 hours and was then distilled again until the volume was about one-half of that originally present (250 ml.) The above process was repeated once more except that the volume was reduced to one-third of the original volume (167 ml.). The reaction mixture was then cooled and filtered. The filter cake consisted of dl-4-acetamido-2-dimethylaminomethylenecyclohexanone formed in the above reaction; weight=6.45 g. Evaporation of the filtrate to dryness yielded a residue, chromatography of a chloroform solution of which over 200 g. of Florisil using chloroform containing increasing amounts of methanol (0-5%) as an eluant, yielded more dl-4-acetamido-2-dimethylaminomethylenecyclohexanone; M.P.=132°-133° C. (from benzene); yield=5.55 g.; total yield=12 g. A reaction mixture was prepared from 15.5 g The benzene was distilled of benzene were added The reaction mixture was heated just below the boiling point of benzene for about 2 hours was then distilled again until the volume The reaction mixture was then cooled filtered formed in the above reaction Evaporation of the filtrate to dryness yielded a residue, chromatography of a chloroform solution of which over 200 g