4-chloro-3-ethoxybenzaldehyde

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

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

Conditions: temp:55.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 4-chloro-N-(4-cyano-piperidin-4-yl)-benzamide hydrochloride (45.03 mg, 0.15 mmol, 1.0 equiv) in ethanol (1 mL), acetic acid (72.1 mg, 1.2 mmol, 8.0 equiv) and N-ethyl diisopropylamine (77.6 mg, 0.6 mmol, 4.0 equiv) was added 4-chloro-3-ethoxy-benzaldehyde (33.2 mg, 0.18 mmol, 1.2 equiv; intermediate B1) and the mixture stirred at 55° C. After 1 h, sodium cyanoborohydride (47.1 mg, 0.75 mmol, 5.0 equiv), dissolved in ethanol (0.5 mL), was added and the mixture stirred at 55° C. over night. Removal of the solvent under reduced pressure and purification by preparative HPLC on reversed phase eluting with a gradient of acetonitrile/water provided 9.7 mg (14%) of the title compound. MS (ISP): 450.2 [M+H]+. was added the mixture stirred at 55° C. over night Removal of the solvent under reduced pressure and purification by preparative HPLC on reversed phase eluting with a gradient of acetonitrile/water

Conditions: temp:55.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 4-chloro-N-(4-cyano-piperidin-4-yl)-benzamide hydrochloride (45.03 mg, 0.15 mmol, 1.0 equiv) in ethanol (1 mL), acetic acid (72.1 mg, 1.2 mmol, 8.0 equiv) and N-ethyl diisopropylamine (77.6 mg, 0.6 mmol, 4.0 equiv) was added 4-chloro-3-ethoxy-benzaldehyde (33.2 mg, 0.18 mmol, 1.2 equiv; intermediate B1) and the mixture stirred at 55° C. After 1 h, sodium cyanoborohydride (47.1 mg, 0.75 mmol, 5.0 equiv), dissolved in ethanol (0.5 mL), was added and the mixture stirred at 55° C. over night. Removal of the solvent under reduced pressure and purification by preparative HPLC on reversed phase eluting with a gradient of acetonitrile/water provided 9.7 mg (14%) of the title compound. MS (ISP): 450.2 [M+H]+. was added the mixture stirred at 55° C. over night Removal of the solvent under reduced pressure and purification by preparative HPLC on reversed phase eluting with a gradient of acetonitrile/water

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

Procedure: The title compound was prepared according to the procedure described for the synthesis of 4-chloro-3-ethoxy-benzaldehyde (intermediate B2) starting from 4-fluoro-3-hydroxy-benzoic acid in 73% overall yield after purification by flash column chromatography on silica eluting with hexane/ethyl acetate (10:1). 1H NMR (300 MHz, DMSO): δ 1.32 (t, J=7.0 Hz, 3H), 4.12 (q, J=7.0 Hz, 2H), 7.34-7.41 (m, 1H), 7.47-7.56 (m, 2H), 9.87 (s, 1H). MS (ISP): 186.1 [M+NH4]+. overall yield after purification by flash column chromatography on silica eluting with hexane/ethyl acetate (10:1)

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

Procedure: To a solution of 4-chloro-3-hydroxy-benzoic acid (3.0 g, 17.4 mmol, 1.0 equiv) in DMF (15 mL) was added K2CO3 (4.81 g, 34.8 mmol, 2.0 equiv) and ethyl iodide (4.03 mL, 5.97 g, 38.2 mmol, 2.2 equiv). The reaction mixture was stirred for 6 h at rt, diluted with water (20 mL) and extracted with ethyl acetate (3×50 mL). The organic phase was dried over Na2SO4 and concentrated to afford 3.6 g (91%) of 4-chloro-3-ethoxy-benzoic acid ethyl ester. The crude ester was then dissolved in THF (20 mL) and cooled to −78° C. under Ar. A solution of diisobutylaluminum hydride (95 mL, 95.0 mmol, 6.0 equiv; 1.0 M solution in THF) was slowly added over a time period of 15 min, the cooling bath removed after completion of addition and the reaction allowed to reach 0° C. After stirring for 1 h, the reaction was cooled to −78° C. and the excess of hydride quenched by cautious addition of a solution of 1 M HCl (10 mL). The mixture was warmed up to rt, the organic phase separated and the aqueous layer extracted with ethyl acetate (3×100 mL). The combined organic phases were dried over Na2SO4 and concentrated by evaporation under reduced pressure providing 2.94 g (100%) of 4-chloro-3-ethoxy-benzyl alcohol. The crude alcohol (2.94 g, 15.75 mmol, 1.0 equiv) was dissolved in dichloromethane (15 mL) and activated MnO2 (5.48 g, 63.0 mmol, 4.0 equiv) was added. The reaction mixture was stirred for 16 h, after which time the reaction was filtered through Hyflo Super Cel and concentrated. The residue was purified by flash column chromatography on silica eluting with heptane/ethyl acetate (4:1) to yield 1.51 g (52%) of the title compound. 1H NMR (300 MHz, CDCl3): δ 1.51 (t, J=7.1 Hz, 3H), 4.19 (q, J=7.1 Hz, 2H), 7.37-7.42 (m, 2H), 7.55 (d, J=9.0 Hz, 1H), 9.94 (s, 1H). after which time the reaction was filtered through Hyflo Super Cel concentrated The residue was purified by flash column chromatography on silica eluting with heptane/ethyl acetate (4:1)

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

Procedure: The title compound was prepared in analogy to the synthesis of 6-[1-(4-methoxy-3-propoxy-benzyl)-piperidin-4-ylamino]-4-trifluoromethyl-nicotinamide (example 197) from 5-(piperidin-4-ylamino)-pyrazine-2-carboxylic acid methyl ester dihydrochloride (intermediate B14) and 4-chloro-3-ethoxy-benzaldehyde (intermediate E2) in a yield of 12.1 mg (21%). MS (ISP): 390.3 [M+H]+.

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

Procedure: The title compound was prepared in analogy to the synthesis of 6-[1-(4-methoxy-3-propoxy-benzyl)-piperidin-4-ylamino]-4-trifluoromethyl-nicotinamide (example 197) from 6-(piperidin-4-ylamino)-4-trifluoromethyl-nicotinic acid methyl ester dihydrochloride (intermediate B7) and 4-chloro-3-ethoxy-benzaldehyde (intermediate E2) in a yield of 13.1 mg (19%). MS (ISP): 458.3 [M+H]+.

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

Procedure: The title compound was prepared in analogy to the synthesis of 2-[1-(3-ethoxy-4-methyl-benzyl)-piperidin-4-ylamino]-isonicotinonitrile (example 189) from 2-(piperidin-4-ylamino)-isonicotinonitrile dihydrochloride (intermediate B15) and 4-chloro-3-ethoxy-benzaldehyde (intermediate E2) in a yield of 3.8 mg (6%). MS (ISP): 371.1 [M+H]+.

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

Procedure: To a solution of 4-chloro-3-hydroxy-benzoic acid (3.0 g, 17.4 mmol, 1.0 equiv) in DMF (15 mL) was added K2CO3 (4.81 g, 34.8 mmol, 2.0 equiv) and ethyl iodide (4.03 mL, 5.97 g, 38.2 mmol, 2.2 equiv). The reaction mixture was stirred for 6 h at rt, diluted with water (20 mL) and extracted with ethyl acetate (3×50 mL). The organic phases were dried over Na2SO4 and concentrated to afford 3.6 g (91%) of 4-chloro-3-ethoxy-benzoic acid ethyl ester. The crude ester was then dissolved in THF (20 mL) and cooled to −78° C. under Ar. A solution of diisobutylaluminium hydride (95 mL, 95.0 mmol, 6.0 equiv; 1.0 M solution in THF) was slowly added over a time period of 15 min, the cooling bath removed on completion of addition and the reaction allowed to reach 0° C. After stirring for 1 h, the reaction was cooled to −78° C. and the excess hydride quenched by cautious addition of a solution of 1 M HCl (10 mL). The mixture was brought to rt, the organic phase separated and the aqueous layer extracted with ethyl acetate (3×100 mL). The combined organic phases were dried over Na2SO4 and concentrated by evaporation under reduced pressure providing 2.94 g (100%) of 4-chloro-3-ethoxy-benzyl alcohol. The crude alcohol (2.94 g, 15.75 mmol, 1.0 equiv) was dissolved in dichloromethane (15 mL) and activated MnO2 (5.48 g, 63.0 mmol, 4.0 equiv) was added. The reaction mixture was stirred for 16 h, after which time the reaction was filtered through Hyflo Super Cel and concentrated. The residue was purified by flash column chromatography on silica eluting with heptane/ethyl acetate (4:1) to yield 1.51 g (52%) of the title compound. 1H NMR (300 MHz, CDCl3): δ 1.51 (t, J=7.1 Hz, 3H), 4.19 (q, J=7.1 Hz, 2H), 7.37-7.42 (m, 2H), 7.55 (d, J=9.0 Hz, 1H), 9.94 (s, 1H). after which time the reaction was filtered through Hyflo Super Cel concentrated The residue was purified by flash column chromatography on silica eluting with heptane/ethyl acetate (4:1)

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

Procedure: The title compound was prepared according to the procedure described for the synthesis of 4-chloro-3-ethoxy-benzaldehyde (intermediate E2, vide infra) starting from 4-fluoro-3-hydroxy-benzoic acid in 73% overall yield after purification by flash column chromatography on silica eluting with hexane/ethyl acetate (10:1). 1H NMR (300 MHz, DMSO): δ 1.32 (t, J=7.0 Hz, 3H), 4.12 (q, J=7.0 Hz, 2H), 7.34-7.41 (m, 1H), 7.47-7.56 (m, 2H), 9.87 (s, 1H). MS (ISP): 186.1 [M+NH4]+. overall yield after purification by flash column chromatography on silica eluting with hexane/ethyl acetate (10:1)

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

Procedure: To a solution of N-[3-(piperidin-4-ylamino)-phenyl]-acetamide dihydrochloride (61.2 mg, 0.2 mmol, 1.0 equiv; intermediate B1), acetic acid (60.1 mg, 1.0 mmol, 5.0 equiv) and triethylamine (40.5 mg, 0.4 mmol, 2.0 equiv) in ethanol (1 mL) was added 4-chloro-3-ethoxy-benzaldehyde (46.1 mg, 0.25 mmol, 1.25 equiv; intermediate E2, vide infra) and the mixture stirred at 50° C. After 1 h, sodium cyanoborohydride (15.1 mg, 0.24 mmol, 1.2 equiv), dissolved in ethanol (1 mL), was added and the mixture stirred at 50° C. over night. Removal of the solvent under reduced pressure and purification by preparative HPLC on reversed phase eluting with a gradient of acetonitrile/water provided 10.0 mg (12%) of the title compound. MS (ISP): 402.3 [M+H]+. was added the mixture stirred at 50° C. over night Removal of the solvent under reduced pressure and purification by preparative HPLC on reversed phase eluting with a gradient of acetonitrile/water