tert-butyl 2-methyl-4-oxo-2,3-dihydropyridine-1-carboxylate

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 3-L four neck round-bottom flask was purged and maintained with a nitrogen atmosphere and a solution of phenyl 4-methoxy-2-methylpyridine-1(2H)-carboxylate (454.1, 70.0 g, 285 mmol, 1.00 equiv) in tetrahydrofuran (1.2 L) was added. The solution was cooled to −78° C. then potassium tert-butoxide (128 g, 1.14 mol, 4.00 equiv) was added portion-wise. The resulting mixture was stirred at 10-15° C. for 20 h then concentrated in vacuo. The residue was dissolved in EtOAc (1.5 L), then carefully quenched with ice water (200 mL). The layers were separated and the aqueous was extracted with additional ethyl acetate (100 mL). The combined organics was washed with aqueous sodium hydroxide (1.5 M, 3×100 mL), aqueous hydrochloric acid (1 M, 2×100 mL), and brine (200 mL), dried (Na2SO4), filtered and concentrated in vacuo. The residue was purified by silica gel chromatography (ethyl acetate/petroleum ether, 1:200-1:20) as the eluent to obtain the title compound as a light yellow oil (31.0 g, 51%). A 3-L four neck round-bottom flask was purged maintained with a nitrogen atmosphere then concentrated in vacuo The residue was dissolved in EtOAc (1.5 L) carefully quenched with ice water (200 mL) The layers were separated the aqueous was extracted with additional ethyl acetate (100 mL) The combined organics was washed with aqueous sodium hydroxide (1.5 M, 3×100 mL), aqueous hydrochloric acid (1 M, 2×100 mL), and brine (200 mL) dried (Na2SO4) filtered concentrated in vacuo The residue was purified by silica gel chromatography (ethyl acetate/petroleum ether, 1:200-1:20) as the eluent

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 3-L four neck round-bottom flask was purged and maintained with a nitrogen atmosphere and a solution of phenyl 4-methoxy-2-methylpyridine-1(2H)-carboxylate (454.1, 70.0 g, 285 mmol, 1.00 equiv) in tetrahydrofuran (1.2 L) was added. The solution was cooled to −78° C. then potassium tert-butoxide (128 g, 1.14 mol, 4.00 equiv) was added portion-wise. The resulting mixture was stirred at 10-15° C. for 20 h then concentrated in vacuo. The residue was dissolved in EtOAc (1.5 L), then carefully quenched with ice water (200 mL). The layers were separated and the aqueous was extracted with additional ethyl acetate (100 mL). The combined organics was washed with aqueous sodium hydroxide (1.5 M, 3×100 mL), aqueous hydrochloric acid (1 M, 2×100 mL), and brine (200 mL), dried (Na2SO4), filtered and concentrated in vacuo. The residue was purified by silica gel chromatography (ethyl acetate/petroleum ether, 1:200-1:20) as the eluent to obtain the title compound as a light yellow oil (31.0 g, 51%). A 3-L four neck round-bottom flask was purged maintained with a nitrogen atmosphere then concentrated in vacuo The residue was dissolved in EtOAc (1.5 L) carefully quenched with ice water (200 mL) The layers were separated the aqueous was extracted with additional ethyl acetate (100 mL) The combined organics was washed with aqueous sodium hydroxide (1.5 M, 3×100 mL), aqueous hydrochloric acid (1 M, 2×100 mL), and brine (200 mL) dried (Na2SO4) filtered concentrated in vacuo The residue was purified by silica gel chromatography (ethyl acetate/petroleum ether, 1:200-1:20) as the eluent

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A 3-L four neck round-bottom flask was purged and maintained with a nitrogen atmosphere and a solution of phenyl 4-methoxy-2-methylpyridine-1(2H)-carboxylate (454.1, 70.0 g, 285 mmol, 1.00 equiv) in tetrahydrofuran (1.2 L) was added. The solution was cooled to −78° C. then potassium tert-butoxide (128 g, 1.14 mol, 4.00 equiv) was added portion-wise. The resulting mixture was stirred at 10-15° C. for 20 h then concentrated in vacuo. The residue was dissolved in EtOAc (1.5 L), then carefully quenched with ice water (200 mL). The layers were separated and the aqueous was extracted with additional ethyl acetate (100 mL). The combined organics was washed with aqueous sodium hydroxide (1.5 M, 3×100 mL), aqueous hydrochloric acid (1 M, 2×100 mL), and brine (200 mL), dried (Na2SO4), filtered and concentrated in vacuo. The residue was purified by silica gel chromatography (ethyl acetate/petroleum ether, 1:200-1:20) as the eluent to obtain the title compound as a light yellow oil (31.0 g, 51%). A 3-L four neck round-bottom flask was purged maintained with a nitrogen atmosphere then concentrated in vacuo The residue was dissolved in EtOAc (1.5 L) carefully quenched with ice water (200 mL) The layers were separated the aqueous was extracted with additional ethyl acetate (100 mL) The combined organics was washed with aqueous sodium hydroxide (1.5 M, 3×100 mL), aqueous hydrochloric acid (1 M, 2×100 mL), and brine (200 mL) dried (Na2SO4) filtered concentrated in vacuo The residue was purified by silica gel chromatography (ethyl acetate/petroleum ether, 1:200-1:20) as the eluent