4-(4-Methylpiperazin-1-yl)aniline → HCID 49839130, compound

195 a) To a cooled, stirred solution of 2-amino-benzoic acid ethyl ester (10.0 g, 60.5 mmol) in ether (50 mL) at 5° C. was added triethylamine (8.44 mL, 60.5 mmol). methanesulfonyl chloride (4.68 mL, 60.5 mmol) in ethyl acetate (50 mL) was added dropwise to the mixture, was stirred for 1 hour at 5° C. then at room temperature for 18 hours. Water (100 mL) was added to the stirring mixture and was extracted with ethyl acetate (3×50 mL). The combined organic was washed with water (2×50 mL) and saturated aqueous sodium chloride. The organic layer was dried over magnesium sulfate, filtered and evaporated. The residue was stirred with warm methanol (30 mL) for 30 minutes and cooled to room temperature. The crystalline material was filtered and rinsed with a minimum of methanol. 2-Methanesulfonylamino-benzoic acid ethyl ester was isolated as a white solid (7.0 g, 48%). 1H NMR (400 MHz, CDCl3, δ, ppm): 10.52 (br s, 1H), 8.07 (d, J=8.0 Hz, 1H), 7.74 (d, J=8.5 Hz, 1H), 7.56 (t, J=7.8 Hz, 1H), 7.13 (t, J=7.7 Hz, 1H), 4.40 (q, J=7.0 Hz, 2H), 3.06 (s, 3H), 1.42 (t, J=7.0 Hz, 3H). MS=266 (M+Na)+. 195 b) To a stirred suspension of 2-methanesulfonylamino-benzoic acid ethyl ester (1.0 g, 4.1 mmol) and cesium carbonate (1.5 g, 4.5 mmol) in acetonitrile (10 mL) was added iodomethane (0.28 mL, 4.5 mmol). The mixture was stirred at room temperature for 18 hours then diluted with dichloromethane (30 mL), filtered through a plug of diatomaceous earth and evaporated. 2-(Methanesulfonyl-methyl-amino)-benzoic acid ethyl ester was isolated as a clear viscous oil (1.08 g, 100%). 1H NMR (400 MHz, CDCl3, δ, ppm): 7.90 (d, J=7.7 Hz, 1H), 7.55 (t, J=7.7 Hz, 1H), 7.47-7.38 (m, 2H), 4.38 (q, J=7.0 Hz, 2H), 3.32 (s, 3H), 2.96 (s, 3H), 1.41 (t, J=7.1 Hz, 3H). MS=280 (M+Na)+. 195 c) To a cooled, stirred suspension of 2.0 M of lithium tetrahydroborate in tetrahydrofuran (0.630 mL, 1.26 mmol) at 5° C. was added dropwise a solution of 2-(methanesulfonyl-methyl-amino)-benzoic acid ethyl ester (1.08 g, 4.20 mmol) in tetrahydrofuran (10 mL). Gas evolution was noted. The mixture was stirred for 10 minutes at 5° C. then at room temperature for 3 hours. The mixture was cooled to 5° C. and saturated aqueous ammonium chloride (5 mL) was added dropwise. Vigorous gas evolution was noted. The mixture was stirred for 15 minutes then warmed to room temperature for 30 minutes. Sodium sulfate was added to granulate aluminium salts. The mixture was diluted with dichloromethane (50 mL), filtered through a plug of diatomaceous earth and evaporated. N-(2-Hydroxymethyl-phenyl)-N-methyl-methanesulfonamide was isolated as a yellow oil (0.931 g, 100%). 1H NMR (400 MHz, CDCl3, δ, ppm): 7.61 (d, J=7.3 Hz, 1H), 7.44-7.35 (m, 2H), 7.28-7.24 (m, 1H), 4.74 (br s, 2H), 3.29 (s, 3H), 2.98 (s, 3H), 2.90-2.81 (m, 1H). MS=238 (M+Na)+. 196 d) To a stirred mixture of N-(2-hydroxymethyl-phenyl)-N-methyl-methanesulfonamide (0.90 g, 4.2 mmol) and carbon tetrabromide (2.40 g, 7.24 mmol) in dry tetrahydrofuran (50 mL) was added triphenylphosphine (1.90 g, 7.23 mmol). The mixture was stirred at room temperature for 18 hours. The volatiles were evaporated under reduced pressure. The residue was triturated with ethyl acetate (30 mL) then filtered and evaporated under reduced pressure. The residue was purified via chromatography (silica gel column 40 g 5%→100% ethyl acetate:hexane). N-(2-Bromomethyl-phenyl)-N-methyl-methanesulfonamide was isolated as pale yellow solid (0.86 g, 74%), 1H NMR (400 MHz, CDCl3, δ, ppm): 7.57-7.52 (m, 1H), 7.41-7.34 (m, 2H), 7.30-7.25 (m, 1H), 5.29-4.30 (br m, 2H), 3.34 (s, 3H), 2.98 (s, 3H). 195 e) To a suspension of 2-amino-[1,2,4]triazolo[1,5-a]pyridin-8-ol (0.20 g, 1.3 mmol) and cesium carbonate (0.47 g, 1.4 mmol) in dry acetone (5 mL, 70 mmol) was added N-(2-bromomethyl-phenyl)-N-methyl-methanesulfonamide (0.40 g, 1.4 mmol). The mixture was stirred for 2 hours at room temperature then heated at 40° C. for 18 hours. The mixture was cooled to room temperature and the volatiles were evaporated. The residue was triturated with water (30 mL). The water was decanted and the waxy solid was dissolved in dichloromethane (30 mL) and washed with water. The organic layer was dried over magnesium sulfate, filtered and evaporated. The recovered material was purified via chromatography (silica gel column 40 g and 0%→10% methanol:dichloromethane). N-[2-(2-Amino-[1,2,4]triazolo[1,5-a]pyridin-8-yloxymethyl)-phenyl]-N-methyl-methanesulfonamide was isolated as an orange viscous oil (0.129 g, 28%). 1H NMR (400 MHz, CDCl3, δ, ppm): 7.96 (d, J=6.7 Hz, 1H), 7.73-7.68 (m, 1H), 7.40-7.28 (m, 3H), 6.88 (d, J=7.8 Hz, 1H), 6.71 (t, J=7.1 Hz, 1H), 5.48 (br s, 2H), 4.44 (s, 2H), 3.31 (s, 3H), 2.99 (s, 3H). 196 f) N-[2-(2-Chloro-[1,2,4]triazolo[1,5-a]pyridin-8-yloxymethyl)-phenyl]-N-methyl-methanesulfonamide was prepared from N-[2-(2-amino-[1,2,4]triazolo[1,5-a]pyridin-8-yloxymethyl)-phenyl]-N-methyl-methanesulfonamide (0.129 g, 0.371 mmol) in a manner analogous to Example 68a. Product isolated as a yellow solid (0.102 g, 75%). 1H NMR (400 MHz, CDCl3, δ, ppm): 8.15 (d, J=6.5 Hz, 1H), 7.73-7.69 (m, 1H), 7.45-7.38 (m, 2H), 7.35-7.30 (m, 1H), 7.03 (d, J=7.9 Hz, 1H), 6.96 (t, J=6.8 Hz, 1H), 5.70-5.30 (m, 2H), 3.32 (s, 3H), 2.99 (s, 3H). MS=367, 369 (MH)+. 195 g) N-Methyl-N-(2-{2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-[1,2,4]triazolo[1,5-a]pyridin-8-yloxymethyl}-phenyl)-methanesulfonamide was prepared from N-[2-(2-chloro-[1,2,4]triazolo[1,5-a]pyridin-8-yloxymethyl)-phenyl]-N-methyl-methanesulfonamide (102.0 mg, 0.2781 mmol) and 4-(4-methyl-piperazin-1-yl)-phenylamine (60.0 mg, 0.314 mmol) with 2,2′-bis-dicyclohexylphosphanyl-biphenyl (30.0 mg, 0.0549 mmol) as the ligand in a manner analogous to Example 2d. Product isolated as a brown foam (0.016 g, 11%). 1H NMR (400 MHz, CDCl3, δ, ppm): 8.07 (d, J=6.7 Hz, 1H), 7.74-7.69 (m, 1H), 7.46 (d, J=8.1 Hz, 2H), 7.43-7.38 (m, 2H), 7.34-7.30 (m, 1H), 6.96 (d, J=8.1 Hz, 2H), 6.90 (d, J=7.8 Hz, 1H), 6.73 (t, J=7.3 Hz, 1H), 6.62 (s, 1H), 5.49 (br s, 2H), 3.32 (s, 3H), 3.18-3.13 (m, 4H), 2.99 (s, 3H), 2.62-2.57 (m, 4H), 2.36 (s, 3H). MS=522 (MH)+.

ORD record

ord-45503b6c1f6843709e2d5f536863b986

Source dataset

uspto-grants-2013_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08501936B2