1-phenylpropane-1,2-dione

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 reaction of dodecyl isobutyrate (6.4 g, 0.025 mole) with 1-phenyl-1,2-propanedione (3.7 g, 0.025 mole) is conducted in the manner described in Example I. Thin layer chromatography of the crude reaction mixture indicated the presence of two main reaction products. High pressure liquid chromatography on silica gel using 2% ethyl acetate in hexane as the eluant yields pure dodecyl 3-hydroxy-2,2-dimethyl-4-oxo-3-phenylpentanoate (IVa) (3.2 g, 32%), b.p. 148° C. (Kugelrohr air bath temperature) at 0.005 mm Hg. Also recovered is pure dodecyl 3-hydroxy-2,2,3-trimethyl-4-oxo-4-phenylbutyrate (IVb) (3.5 g, 35%), b.p. 145° C. (Kugelrohr air bath temperature) at 0.005 mm Hg. Thin layer chromatography of the crude reaction mixture

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

Procedure: The reaction of dodecyl isobutyrate (6.4 g, 0.025 mole) with 1-phenyl-1,2-propanedione (3.7 g, 0.025 mole) is conducted in the manner described in Example I. Thin layer chromatography of the crude reaction mixture indicated the presence of two main reaction products. High pressure liquid chromatography on silica gel using 2% ethyl acetate in hexane as the eluant yields pure dodecyl 3-hydroxy-2,2-dimethyl-4-oxo-3-phenylpentanoate (IVa) (3.2 g, 32%), b.p. 148° C. (Kugelrohr air bath temperature) at 0.005 mm Hg. Also recovered is pure dodecyl 3-hydroxy-2,2,3-trimethyl-4-oxo-4-phenylbutyrate (IVb) (3.5 g, 35%), b.p. 145° C. (Kugelrohr air bath temperature) at 0.005 mm Hg. Thin layer chromatography of the crude reaction mixture

Conditions: temp:50.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 5.32 kg of 1-phenylpropane-1,2-dione (98.6% by G.C. equivalent to 5.24 kg, 35.4 mole) were dissolved in 36 liters of chloroform and the solution was heated to 50° C. A solution of 5.66 kg (35.4 mole) of bromine in 8 liters of chloroform was added slowly to maintain a gentle reflux and immediate decolorization of the bromine (approximately 6 hours). The solution was cooled to room temperature overnight and was washed with 20 liters of saturated sodium bicarbonate solution and 20 liters of water and dried over sodium sulfate. The solvent was removed under vacuum to obtain 8.2 kg (100% yield) of a green/yellow oil which was used directly for subsequent reactions after estimation of its purity (approximately 75% by G.C. or N.M.R.). to maintain a gentle reflux The solution was cooled to room temperature overnight was washed with 20 liters of saturated sodium bicarbonate solution and 20 liters of water dried over sodium sulfate The solvent was removed under vacuum

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

Procedure: 6.0 kg (44.78 moles) of propiophenone and 92 g of anhydrous aluminum chloride were added to 6 liters of ether followed by 17.2 kg (107.5 mole) of bromine at a rate to maintained a gentle reflux. When the addition was complete (approximately 6 hours), the mixture was heated to reflux overnight and then the solvent was removed under vacuum to obtain a lachrymatory dark red/orange oil. The oil was slowly added to a solution of 2.81 kg (122.2 mmole)of sodium in 45 l of methanol while maintaining the temperature below 20° C. When the addition was complete, 12.5 liters of concentrated hydrochloric acid were added and the mixture was stirred at room temperature for 1 hour. The precipitate was filtered off and the filtrate reduced in volume to approximately 25 liters by distillation of the methanol. The residue was partitioned between 10 liters of chloroform and 10 liters of water. Then, the organic phase was separated and the aqueous phase extracted twice with 5 liters of chloroform. The combined chloroform solutions were dried over sodium sulfate and evaporated to dryness. The residue was fractionally distilled under vacuum through a 30 cm Fenske column to obtain 5.7 kg of 1-phenylpropane-1,2-dione (86% yield) and a boiling point of 77°-85° C. at 1-2 mm Hg. to maintained a gentle reflux When the addition (approximately 6 hours) the mixture was heated to reflux overnight the solvent was removed under vacuum to obtain a lachrymatory dark red/orange oil while maintaining the temperature below 20° C When the addition The precipitate was filtered off the filtrate reduced in volume to approximately 25 liters by distillation of the methanol The residue was partitioned between 10 liters of chloroform and 10 liters of water Then, the organic phase was separated the aqueous phase extracted twice with 5 liters of chloroform The combined chloroform solutions were dried over sodium sulfate evaporated to dryness The residue was fractionally distilled under vacuum through a 30 cm Fenske column

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

Procedure: The procedure is as in Example 2 for the preparation of ethyl 4-dimethylamino-2-oxo-3-butenoate, starting with 1-phenyl-1,2-propanedione (25 g) and N,N-dimethylformamide diethyl acetal (28.3 g). After purification by chromatography on a silica column with ethyl acetate as eluent, 4-dimethylamino-1-phenyl-3-butene-1,2-dione (9.3 g), m.p. 88° C., is obtained. After purification by chromatography on a silica column with ethyl acetate as eluent

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

Procedure: The procedure is as in Example 2 for the preparation of ethyl 4-dimethylamino-2-oxo-3-butenoate, starting with 1-phenyl-1,2-propanedione (25 g) and N,N-dimethylformamide diethyl acetal (28.3 g). After purification by chromatography on a silica column with ethyl acetate as eluent, 4-dimethylamino-1-phenyl-3-butene-1,2-dione (9.3 g), m.p. 88° C., is obtained. After purification by chromatography on a silica column with ethyl acetate as eluent

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

Procedure: In a 200 ml of Erlenmeyer flask were placed 5.0 g (26.5 mmols) of 2,3-diaminonaphthoquinone and 75 ml of acetic acid/water (1/1), a solution composed of 5.9 g (39.8 mmols) of 1-phenyl-1,2-propanedione and 25 ml of acetic acid/water (1/1) was added dropwise to the mixture under ice-cooling over a period of about 10 minutes, and after stirring the mixture for 5 minutes, yellow precipitates thus formed were collected by filtration and washed with water. The precipitates were dissolved in methylene chloride, and after purifying the product with silica gel short column (eluted by methylene chloride), the product was recrystallized from methylene chloridemethanol to provide 6.22 g (78%) of 2-methyl-3-phenylnaphthoquinone (Compound Id-11) as a yellow powder. Melting point 235°-236° C. The infrared spectrum of the compound obtained is shown in FIG. 7. was added dropwise to the mixture under ice- cooling over a period of about 10 minutes yellow precipitates thus formed were collected by filtration washed with water The precipitates were dissolved in methylene chloride after purifying the product with silica gel short column (eluted by methylene chloride) the product was recrystallized from methylene chloridemethanol