diethyl but-2-ynedioate

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: A solution of 10.0 g (0.09 mole) 4-fluoroaniline 7 and 8.0 g (0.047 mole) diethylacetylene dicarboxylate 8 is stirred at room temperature for 72 hours. The crude product is purified by flash chromatography using silica gel eluted initially with ethyl acetate:hexane (1:4) and finally with ethyl acetate. The fractions containing the product are combined and concentrated under reduced pressure to give 9 as a yellow oil. The crude product is purified by flash chromatography eluted initially with ethyl acetate:hexane (1:4) and finally with ethyl acetate The fractions containing the product concentrated under reduced pressure

Conditions: temp:80.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a stirred solution of intermediate 23, 2-(2-chloroethoxy)-2-methylpropanenitrile (14.7 g, 0.10 mole) and NaI (1.5 g, 10 mmol) in ethanol (50 mL) was added an aqueous solution (50%) of hydroxylamine (18.4 g, 0.30 mole) resulting in an exothermic reaction. Following this the reaction mixture was heated at 80° C. for 2 h. Upon cooling to room temperature the solvent was removed. The resulting residue was dissolved in 1:1 ethanol/H2O (100 mL) and cooled in an ice bath. To this was added diethyl acetylenedicarboxylate (17.6 mL, 0.110 mole) over 10 min. The reaction mixture was allowed to warm to room temperature and stirred for 1 h. Following this, it was diluted with ethyl acetate (250 mL), washed with H2O (2×100 mL), brine (50 mL), dried over Na2SO4, filtered and concentrated to give the crude product as a yellow oil. Flash chromatography on a silica gel column, eluting with 20–40% ethyl acetate/Hexanes, provided the title compound as a viscous pale yellow oil (15.29 g, 48.6% yield). 1H NMR (500 MHz, CDCl3) δ ppm: 4.35–4.28 (2H, m), 4.18–4.12 (2H, m), 3.60–3.56 (1H, m), 3.51–3.47 (1H, m), 3.30 (1H, d, J=16.2 Hz), 2.94 (1H, d, J=16.2 Hz), 1.52 (3H, s), 1.51 (3H, s), 1.29 (3H, t, J=7.0 Hz), 1.24 (3H, t, J=7.0 Hz). LCMS (M+H) calcd for C14H23N2O7: 315.16; found: 315.33. resulting in an exothermic reaction Upon cooling to room temperature the solvent was removed The resulting residue was dissolved in 1:1 ethanol/H2O (100 mL) cooled in an ice bath to warm to room temperature washed with H2O (2×100 mL), brine (50 mL) dried over Na2SO4 filtered concentrated to give the crude product as a yellow oil Flash chromatography on a silica gel column, eluting with 20–40% ethyl acetate/Hexanes

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

Procedure: To a solution of 2-fluoro-3-hydrazinopyridine (30.0 g) in ethanol (472 mL) were added sodium carbonate (65.2 g) and diethyl but-2-ynedioate (40.2 g). After refluxing for 18 hr, the mixture was cooled to room temperature, treated with 2 mol/L hydrochloric acid, and extracted twice with ethyl acetate. The extract was dried over anhydrous sodium sulfate and concentrated under reduced pressure. The residue was suspended in diethyl ether, and the obtained solid was collected by filtration and dried under reduced pressure to give the title compound as a yellow solid (yield 20.0 g, yield 34%). After refluxing for 18 hr extracted twice with ethyl acetate The extract was dried over anhydrous sodium sulfate concentrated under reduced pressure the obtained solid was collected by filtration dried under reduced pressure

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

Procedure: 2-Bromo-4,5-methylenedioxybenzaldehyde dimethyl-acetal, 3,4-diisopropoxybenzaldehyde and diethyl acetylene-dicarboxylate are treated in the same manner as described in Example 1, whereby 1-(3,4-diisopropoxyphenyl)-2,3-bis(ethoxycarbonyl)-4-hydroxy-6,7-methylenedioxynaphthalene is obtained.

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

Procedure: 2-Bromo-3,4,5-trimethoxybenzaldehyde dimethylacetal, 3,4-dimethoxybenzaldehyde and diethyl acetylenedicarboxylate are treated in the same manner as described in Example 1-(1) & (2), whereby 1-(3,4-dimethoxyphenyl)-2,3-bis(ethoxycarbonyl)-4-hydroxy-6,7,8-trimethoxynaphthalene is obtained as colorless crystals.

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

Procedure: Treatment of 3-iodo-5-methylaniline (4.1 g) with diethylacetylene dicarboxylate (2.8 ml) as described in Example 1b, gave a mixture (3.0 g) of ethyl 5-iodo-7-methyl-4-oxo-1,4-dihydroquinoline-2-carboxylate [δ (360 MHz, DMSO-d6) 1.50 (3H, t, CH2CH3), 2.76 (3H, s, CH3), 4.41 (2H, q, CH2CH3), 6.58 (1H, s, 3-H), 7.74 (1H, s, 6-H) and 7.78 (1H, s, 8-H)] and ethyl 7-iodo-5-methyl-4-oxo-1,4-dihydroquinoline-2-carboxylate [δ (360 MHz, DMSO-d6) 1.33 (3H, t, CH2CH3), 2.72 (3H, s, CH3), 4.41 (2H, q, CH2CH3), 6.54 (1H, bs, 3-H), 7.40 (1H, s, 6-H) and 8.20 (1H, s, 8-H)].

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

Procedure: Treatment of 3-chloro-5-iodoaniline (1.4 g) with diethylacetylene dicarboxylate (0.93 ml), as described in Example 1b, gave a mixture (1.83 g) of ethyl 5-chloro-7-iodo-4-oxo-1,4-dihydroquinoline-2-carboxylate [δ (360 MHz, DMSO-d6) 1.37 (3H, t, CH2CH3), 4.40 (2H, q, CH2CH3), 6.59 (1H, s, 3-H), 7.61 (1H, s, 6-H), 8.32 (1H, s, 8-H) and 11.90 (1H, bs, NH)] and ethyl 7-chloro-5-iodo-4-oxo-1,4-dihydroquinoline-2-carboxylate [δ (360 MHz, DMSO-d6) 1.37 (3H, t, CH2CH3), 4.40 (2H, q, CH2CH3), 6.63 (1H, s, 3-H), 7.90 (1H, s, 6-H), 8.04 (1H, s, 8-H) and 11.90 (1H, bs, NH)].

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

Procedure: Reaction of 3-chloro-5-ethylaniline (0.9 g) with diethylacetylene dicarboxylate (0.93 ml) as described in Example 1b gave a mixture of the two 5,7-regioisomers (800 mg). The isomers were separated by silica chromatography to give ethyl 7-chloro-5-ethyl-4-oxo-1,4-dihydroquinoline-2 -carboxylate (250 mg), mp 222°-3° C.; δ (360 MHz, DMSO-d6) 1.15 (3H, t, CH2CH3), 1.36 (3H, t, CO2CH2CH3), 3.25 (2H, q, CH2CH3), 4.42 (2H, q, CO2CH2) 6.57 (1H, s, 3-H), 7.12 (1H, d, 8-H), 7.87 (1H, d, 6-H) and 11.75 (1H, bs, NH); and ethyl 5-chloro-7-ethyl-4-oxo-1,4-dihydroquinoline-2-carboxylate (200 mg), mp 182°-3° C.; δ (360 MHz, DMSO-d6) 1.21 (3H, t, CH2CH3), 1.35 (3H, t, CO2CH2CH3), 2.67 (2H, q, CH2CH3), 4.40 (2H, q, CO2CH2) 6.56 (1H, s, 3-H), 7.28 (1H, d, 6-H), 7.73 (1H, d, 8-H) and 11.78 (1H, bs, NH). gave a mixture of the two 5,7-regioisomers (800 mg) The isomers were separated by silica chromatography