propyl (Z)-3-aminobut-2-enoate

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

Procedure: A solution of 100 mg (0.45 mmol) of 5,6-difluoro-2-methyl-4-oxo-4H-chromene-8-carbaldehyde in 5 ml of 2-propanol is mixed with 46.9 mg (0.45 mmol) of sodium 1-cyanoprop-1-en-2-olate, 63.88 mg (0.45 mmol) of propyl 3-aminocrotonate and 0.04 ml (0.67 mmol) of acetic acid and stirred under reflux for 3 h. After cooling, the mixture is concentrated. The residue is taken up in dichloromethane and washed with water. The organic phase is dried over sodium sulfate and concentrated. The resulting residue is crystallized from diethyl ether. The beige-colored crystals are filtered off with suction and dried at 40° C. in a vacuum drying oven. 74.6 mg (40.35% of theory) of the title compound are obtained. under reflux for 3 h After cooling the mixture is concentrated washed with water The organic phase is dried over sodium sulfate concentrated The resulting residue is crystallized from diethyl ether The beige-colored crystals are filtered off with suction dried at 40° C. in a vacuum drying oven

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

Procedure: A solution of 100 mg (0.45 mmol) of 5,6-difluoro-2-methyl-4-oxo-4H-chromene-8-carbaldehyde in 5 ml of 2-propanol is mixed with 46.9 mg (0.45 mmol) of sodium 1-cyanoprop-1-en-2-olate, 63.88 mg (0.45 mmol) of propyl 3-aminocrotonate and 0.04 ml (0.67 mmol) of acetic acid and stirred under reflux for 3 h. After cooling, the mixture is concentrated. The residue is taken up in dichloromethane and washed with water. The organic phase is dried over sodium sulfate and concentrated. The resulting residue is crystallized from diethyl ether. The beige-colored crystals are filtered off with suction and dried at 40° C. in a vacuum drying oven. 74.6 mg (40.35% of theory) of the title compound are obtained. under reflux for 3 h After cooling the mixture is concentrated washed with water The organic phase is dried over sodium sulfate concentrated The resulting residue is crystallized from diethyl ether The beige-colored crystals are filtered off with suction dried at 40° C. in a vacuum drying oven

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

Procedure: A solution of 100 mg (0.49 mmol) of 5-fluoro-2-methyl-4-oxo-4H-chromene-8-carbaldehyde in 5 ml of 2-propanol is mixed with 50.96 mg (0.49 mmol) of sodium 1-cyanoprop-1-en-2-olate, 69.45 mg (0.49 mmol) of propyl 3-aminocrotonate and 0.04 ml (0.73 mmol) of acetic acid and stirred under reflux for 3 h. After cooling, the mixture is concentrated. The residue is taken up in dichloromethane and washed with water. The organic phase is dried over sodium sulfate and concentrated. The resulting residue is crystallized from diethyl ether. The beige-colored crystals are filtered off with suction and dried at 40° C. in a vacuum drying oven. 112.9 mg (58.7% of theory) of the title compound are obtained. under reflux for 3 h After cooling the mixture is concentrated washed with water The organic phase is dried over sodium sulfate concentrated The resulting residue is crystallized from diethyl ether The beige-colored crystals are filtered off with suction dried at 40° C. in a vacuum drying oven

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

Procedure: 240 mg (0.62 mmol) of 1-(2-methoxyphenyl)-2-[(2-methyl-4-oxo-4H-chromen-8-yl)methylene]-butane-1,3-dione are heated with 94 mg (0.62 mmol) of n-propyl 3-aminocrotonate in 5 ml of 2-propanol under reflux overnight. The solvent is removed in vacuo, and the residue is purified by preparative HPLC. 108 mg (33% of theory) of the title compound are obtained. under reflux overnight The solvent is removed in vacuo the residue is purified by preparative HPLC

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

Procedure: 245 mg (0.67 mmol) of 1-(3-methoxyphenyl)-2-[(2-methyl-4-oxo-4H-chromen-8-yl)methylene]-butane-1,3-dione are heated with 96 mg (0.67 mmol) of n-propyl 3-aminocrotonate in 5 ml of 2-propanol under reflux overnight. The solvent is removed in vacuo, and the residue is purified by preparative HPLC. 94 mg (28% of theory) of the title compound are obtained. under reflux overnight The solvent is removed in vacuo the residue is purified by preparative HPLC

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

Procedure: 230 mg (0.63 mmol) of 1-(4-methoxyphenyl)-2-[(2-methyl-4-oxo-4H-chromen-8-yl)methylene]-butane-1,3-dione are heated with 90 mg (0.63 mmol) of n-propyl 3-aminocrotonate in 5 ml of 2-propanol under reflux overnight. The solvent is removed in vacuo, and the residue is purified by preparative HPLC. 74 mg (24% of theory) of the title compound are obtained. under reflux overnight The solvent is removed in vacuo the residue is purified by preparative HPLC

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

Procedure: 40 mg (0.18 mmol) of 5-chloro-2-methyl-4-oxo-4H-chromene-8-carbaldehyde are dissolved with 31 mg (0.18 mmol) of 2,4-pentanedione, 25 mg (0.18 mmol) of n-propyl 3-aminocrotonate and 11 mg (0.18 mmol) of acetic acid in 2 ml of 2-propanol and heated under reflux under argon for 10 h. The solvent is removed in vacuo, and the residue is purified by preparative HPLC. 33 mg (42% of theory) of the title compound are obtained as a yellow solid. heated under reflux under argon for 10 h The solvent is removed in vacuo the residue is purified by preparative HPLC

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

Procedure: 250 mg (0.75 mmol) of 2-[(2-methyl-4-oxo-4H-chromen-8-yl)methylene]-1-phenylbutane-1,3-dione are dissolved with 143 mg (1.0 mmol) of n-propyl 3-aminocrotonate in 5 ml of ethanol and heated under reflux under argon for 24 h. The reaction solution is purified by preparative HPLC. heated under reflux under argon for 24 h The reaction solution is purified by preparative HPLC

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

Procedure: A solution of 100 mg (0.45 mmol) of 5,6-difluoro-2-methyl-4-oxo-4H-chromene-8-carbaldehyde in 5 ml of 2-propanol is mixed with 46.9 mg (0.45 mmol) of sodium 1-cyanoprop-1-en-2-olate, 63.88 mg (0.45 mmol) of propyl 3-aminocrotonate and 0.04 ml (0.67 mmol) of acetic acid and stirred under reflux for 3 h. After cooling, the mixture is concentrated. The residue is taken up in dichloromethane and washed with water. The organic phase is dried over sodium sulfate and concentrated. The resulting residue is crystallized from diethyl ether. The beige-colored crystals are filtered off with suction and dried at 40° C. in a vacuum drying oven. 74.6 mg (40.35% of theory) of the title compound are obtained. under reflux for 3 h After cooling the mixture is concentrated washed with water The organic phase is dried over sodium sulfate concentrated The resulting residue is crystallized from diethyl ether The beige-colored crystals are filtered off with suction dried at 40° C. in a vacuum drying oven

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

Procedure: A solution of 100 mg (0.49 mmol) of 5-fluoro-2-methyl-4-oxo-4H-chromene-8-carbaldehyde in 5 ml of 2-propanol is mixed with 50.96 mg (0.49 mmol) of sodium 1-cyanoprop-1-en-2-olate, 69.45 mg (0.49 mmol) of propyl 3-aminocrotonate and 0.04 ml (0.73 mmol) of acetic acid and stirred under reflux for 3 h. After cooling, the mixture is concentrated. The residue is taken up in dichloromethane and washed with water. The organic phase is dried over sodium sulfate and concentrated. The resulting residue is crystallized from diethyl ether. The beige-colored crystals are filtered off with suction and dried at 40° C. in a vacuum drying oven. 112.9 mg (58.7% of theory) of the title compound are obtained. under reflux for 3 h After cooling the mixture is concentrated washed with water The organic phase is dried over sodium sulfate concentrated The resulting residue is crystallized from diethyl ether The beige-colored crystals are filtered off with suction dried at 40° C. in a vacuum drying oven