4-((6-(2-(2,4-DIFLUOROPHENYL)-1,1-DIFLUORO-2-HYDROXY-3-(5-MERCAPTO-1H-1,2,4-TRIAZOL-1-YL)PROPYL)PYRIDIN-3-YL)OXY)BENZONITRILE AND PROCESSES OF PREPARATION

Abstract

Provided herein are methods for the preparation of 4-((6-(2-(2,4-difluorophenyl)-1, 1-difluoro-2-hydroxy-3-(5-mer-capto-1H-1,2,4-triazol-1-yl)propyl)pyridin-3-yl)oxy)benzonitrile.

Claims

1. A method of making a compound of Formula I comprising: ##STR00012## contacting a compound of Formula II ##STR00013## with a base and an acid.

2. The method of claim 1, wherein the base is selected from the group including metal carbonates, metal alkoxides, and metal hydroxides.

3. The method of claim 1, wherein the base is selected from sodium hydroxide or potassium hydroxide.

4. The method of claim 1, wherein the acid is selected from the group including HCl, HBr, H.sub.2SO.sub.4, H.sub.3PO.sub.4 and HNO.sub.3.

5. The method of claim 1, further comprising the step of contacting a compound of Formula III: ##STR00014## wherein R is H or t-BuO(CO); with formic acid to prepare the compound of Formula II.

6. The method of claim 5 wherein the contacting is carried out at between about 10 C. and about 100 C.

7. A compound consisting of: ##STR00015##

Description

DETAILED DESCRIPTION

[0014] 4-((6-(2-(2,4-Difluorophenyl)-1,1-difluoro-2-hydroxy-3-(5-mercapto-1H-1,2,4-triazol-1-yl)propyl)pyridin-3-yl)oxy)benzonitrile (I) may be prepared from 1-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)-2-formylhydrazine-1-carbothioamide (II) as shown in Example 1.

Example 1: Preparation of 4-((6-(2-(2,4-difluorophenyl)-1,1-difluoro-2-hydroxy-3-(5-mercapto-1H-1,2,4-triazol-1-yl)propyl)pyridin-3-yl)oxy)benzonitrile (I)

[0015] ##STR00006##

[0016] To 1-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)-2-formylhydrazine-1-carbothioamide (II) (0.73 g, 1.405 mmol) was added 2 N sodium hydroxide (3.51 mL, 7.03 mmol) and the reaction was stirred at room temperature for 1 h over which time it went from a slurry to a clear solution. HCl (2 N, 3.6 mL) was added causing a white precipitate to form (pH 2). The precipitate was isolated by filtration and the solid was rinsed with water. The material was allowed to air dry giving 4-((6-(2-(2,4-difluorophenyl)-1,1-difluoro-2-hydroxy-3-(5-mercapto-1H-1,2,4-triazol-1-yl)propyl)pyridin-3-yl)oxy)benzonitrile (I) as a white solid (676.8 mg, 1.350 mmol, 96% yield). .sup.1H NMR (400 MHz, CDCl.sub.3) 8.44 (d, J=2.7 Hz, 1H), 7.72-7.65 (m, 2H), 7.62 (s, 1H), 7.58 (d, J=8.6 Hz, 1H), 7.50-7.36 (m, 2H), 7.10-7.02 (m, 2H), 6.80 (ddd, J=11.5, 8.6, 2.6 Hz, 1H), 6.76-6.69 (m, 1H), 5.93 (s, 1H), 5.31-5.21 (m, 2H). 19F NMR (376 MHz, CDCl.sub.3) -103.15 (ddd, J=31.2, 23.4, 9.4 Hz), -108.46 (d, J=29.1 Hz), -109.02 (d, J=23.2 Hz), -109.39 (d, J=9.2 Hz). ESIMS m/z 502.0 [(M+H)+].

[0017] Suitable bases for use in this process step may include metal carbonates, metal alkoxides, and metal hydroxides such as, for example, sodium carbonate, potassium carbonate, sodium methoxide, potassium methoxide, sodium hydroxide and potassium hydroxide.

[0018] Suitable acids for use in this process step may include, for example, hydrochloric acid (HCl), hydrobromic acid (HBr), acetic acid, formic acid, sulfuric acid (H.sub.2SO.sub.4), phosphoric acid (H.sub.3PO.sub.4) and nitric acid (HNO.sub.3).

[0019] 1-(3-(5-(4-Cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)-2-formylhydrazine-1-carbothioamide (II) may be prepared from 1-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carbothioamide (III, RH) as shown in Example 2.

Example 2: Preparation of 1-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)-2-formylhydrazine-1-carbothioamide (II)

[0020] ##STR00007##

[0021] To 1-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carbothioamide (III, RH) (0.25 g, 0.509 mmol) was added formic acid (0.780 mL, 20.35 mmol) and the reaction mixture was stirred at room temperature for 22 h. The reaction mixture was partitioned between ethyl acetate and brine and the layers separated. The organic layer was washed with saturated aqueous sodium bicarbonate. The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated giving a white solid (240 mg). Dichloromethane (3 mL) was added to give a slurry, which was filtered and the solid was dried under vacuum giving 1-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)-2-formylhydrazine-1-carbothioamide (II) as a white solid (207.3 mg, 0.379 mmol, 75% yield). .sup.1H NMR (400 MHz, DMSO-d.sub.6) 10.09 (s, 1H), 8.45 (d, J=2.7 Hz, 1H), 7.99-7.84 (m, 2H), 7.69 (dd, J=8.6, 2.9 Hz, 1H), 7.56 (dt, J=24.6, 9.2 Hz, 2H), 7.23-7.15 (m, 2H), 7.11 (td, J=10.5, 9.1, 2.4 Hz, 1H), 7.03 (d, J=9.6 Hz, 1H), 6.56 (s, 1H), 5.45 (s, 1H), 4.44 (s, 1H). 19F NMR (376 MHz, DMSO-d.sub.6) -105.46, -108.14, -108.54, -111.06 (d, J=9.0 Hz). ESIMS m/z 520.1 [(M+H).sup.+].

[0022] Alternatively, 1-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)-2-formylhydrazine-1-carbothioamide (II) may be prepared from t-butyl 2-carbamothioyl-2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (III, R=t-BuO(CO)) as shown in Example 3.

Example 3: Preparation of 1-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)-2-formylhydrazine-1-carbothioamide (II)

[0023] ##STR00008##

[0024] To t-butyl 2-carbamothioyl-2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (III, R=t-BuO(CO)). (1.33 g, 2.248 mmol) was added formic acid (3.45 mL, 90 mmol) and the reaction was stirred at room temperature for 22 h. The reaction was partitioned between ethyl acetate and water and the layers separated. The organic layer was washed with saturated aqueous sodium bicarbonate. The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated to an oil. Dichloromethane was added and the material concentrated to a solid.

[0025] Dichloromethane (5 mL) was added forming a white precipitate that was isolated by filtration and washed with dichloromethane. The white solid was dried under vacuum giving 1-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)-2-formylhydrazine-1-carbothioamide (II) (733.4 mg, 1.412 mmol, 63% yield). The analytical data matched that for the product prepared in Example 2.

[0026] The processes exemplified in Examples 2 and 3 may be conducted at temperatures between about 10 C. and about 100 C., or between about 20 C. and about 50 C., and may be conducted using solvents such as THF, 2-Me-THF, dioxane, DME, acetonitrile, and mixtures thereof.

[0027] 1-(3-(5-(4-Cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carbothioamide (III, RH) may be prepared from t-butyl 2-carbamothioyl-2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (III, R=t-BuO(CO)) as shown in Example 4.

Example 4: Preparation of 1-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carbothioamide (III, RH)

[0028] ##STR00009##

[0029] To a slurry of t-butyl 2-carbamothioyl-2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (III, R=t-BuO(CO)) (2 g, 3.38 mmol) in methanol (16.90 mL) was added hydrogen chloride (4 M in dioxane; 4.23 mL, 16.90 mmol) and the reaction was heated to 50 C. After 1 h the reaction was quenched with saturated sodium bicarbonate and extracted with ethyl acetate. The organic layer was washed with water and brine, dried over anhydrous sodium sulfate, filtered, and concentrated giving a yellow foam (1.65 g). The crude material was dissolved in dichloromethane and purified by silica gel column chromatography using ethyl acetate/hexanes as the eluent. Product containing fractions were collected and concentrated giving 1-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carbothioamide (III, RH) as a white foam (1.38 g, 2.81 mmol, 83% yield). .sup.1H NMR (400 MHz, CDCl.sub.3) 8.33 (d, J=2.7 Hz, 1H), 7.74-7.62 (m, 3H), 7.56 (d, J=8.6 Hz, 1H), 7.39 (dd, J=8.7, 2.7 Hz, 1H), 7.08-7.00 (m, 2H), 6.90-6.75 (m, 2H), 6.49 (s, 1H), 5.25 (d, J=15.5 Hz, 1H), 4.89 (d, J=15.5 Hz, 1H). .sup.19F NMR (376 MHz, CDCl.sub.3) -104.41 (t, J=26.1 Hz), -108.49 (d, J=77.7 Hz), -109.07 (d, J=8.9 Hz). ESIMS m/z 492.1 [(M+H)+].

[0030] Suitable acids for use in this process step may include hydrochloric acid (HCl), hydrobromic acid (HBr), sulfuric acid (H.sub.2SO.sub.4), phosphoric acid (H.sub.3PO.sub.4), nitric acid (HNO.sub.3), and trifluoroacetic acid (TFA).

[0031] Suitable solvents for use in this process step may include alcohols such as, for example, methanol, ethanol, isopropanol, dioxane, THF, DME, and MeCN.

[0032] The process exemplified in Example 4 may be conducted at temperatures between about 10 C. and about 100 C., or between about 20 C. and about 70 C.

Example 3: Preparation of t-butyl 2-carbamothioyl-2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (III)

[0033] ##STR00010##

[0034] Method A:

[0035] To t-butyl 2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (IV) (5 g, 9.39 mmol) in THF (31.3 mL) at 0 C. was added benzoyl isothiocyanate (1.199 mL, 8.92 mmol). After 30 min additional benzoyl isothiocyanate (0.1 mL, 0.74 mmol) was added. The benzoyl intermediate was identified by LCMS (ESIMS m/z 696.1 [(M+H)+]). After an additional 30 min, anhydrous hydrazine (1.47 mL, 46.9 mmol) was added. The mixture was stirred at 0 C. for 1 h then room temperature for 30 min. The reaction was diluted with ethyl acetate and washed with sat. ammonium chloride. The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated to a pale yellow oil. Methanol (25 mL) was added to the oil and after a few minutes of stirring a white precipitate had formed. The slurry was filtered and the solid rinsed with methanol giving t-butyl 2-carbamothioyl-2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (III) (4.29 g, 7.25 mmol, 77% yield) as a white solid. .sup.1H NMR (400 MHz, DMSO-d.sub.6) 8.76 (s, 1H), 8.45 (d, J=11.9 Hz, 2H), 7.96-7.86 (m, 2H), 7.70 (dd, J=8.6, 2.8 Hz, 2H), 7.58 (d, J=8.4 Hz, 1H), 7.53-7.40 (m, 1H), 7.22-7.15 (m, 2H), 7.12 (t, J=11.0 Hz, 1H), 7.01 (d, J=8.8 Hz, 1H), 6.37 (s, 1H), 5.45 (d, J=15.7 Hz, 1H), 4.47 (d, J=15.3 Hz, 1H), 1.40 (s, 9H). .sup.19F NMR (376 MHz, DMSO-d.sub.6) -104.72 (d, J=122.8 Hz), -107.49-109.12 (m), 111.08-111.85 (m). ESIMS m/z 592.2 [(M+H)+].

[0036] Method B:

[0037] To a solution of t-butyl 2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (IV, 1 g, 1.596 mmol) in ethyl acetate (9.4 mL) was added isothiocyanatotrimethylsilane (0.540 mL, 3.83 mmol) and the reaction was stirred at 80 C. for 18 h. NMR indicated incomplete conversion so additional isothiocyanatotrimethylsilane (0.540 mL, 3.83 mmol) was added and the reaction stirred at 80 C. for 6 h. NMR indication the reaction was still incomplete so more isothiocyanatotrimethylsilane (0.540 mL, 3.83 mmol) was added and the reaction stirred at 80 C. for 17 h. The reaction was allowed to cool to room temperature and 1 N HCl (10 mL) was added. The phases were separated and the organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated to a yellow foam. The yellow foam was dissolved in methylene chloride and purified by silica gel column chromatography eluting with 0-60% ethyl acetate/hexanes. Product containing fractions were collected and concentrated giving t-butyl 2-carbamothioyl-2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (III) as a yellow foam (460 mg, 0.778 mmol, 49% yield). Analytical data was consistent with that of previously obtained samples.

[0038] Organic isothiocyanates for use in this process step may include acyl isothiocyanates such as, for example, benzoyl isothiocyanate and silyl isothiocyanates such as, for example, trimethylsilyl isothiocyanate.

[0039] Cleaving reagents used to remove the R-group, wherein R is benzoyl, from the unisolated intermediate to prepare the compound of Formula III, may be selected from the group including hydrazine, ammonia, sodium methoxide, and methylamine. Cleaving reagents used to remove the R-group, wherein R is trimethylsilyl, from the unisolated intermediate to prepare the compound of Formula III, may be selected from: a) fluoride compounds such as, for example, a tetraalkylammonium fluoride and potassium fluoride, and b) an acid such as, for example, hydrochloric acid (HCl), hydrobromic acid (HBr), or sulfuric acid (H.sub.2SO.sub.4).

[0040] The contacting of the compound of Formula IV with the organic isothiocyanate may be carried out between about 20 C. and about 100 C., and the contacting with the cleaving reagent may be carried out between about 20 C. and about 100 C.

[0041] Solvents for use in this process step may include one or more than one of THF (tetrahydrofuran), EtOAc, 2-Me-THF, dioxane, MeCN (acetonitrile), and DME (1,2-dimethoxyethane).

[0042] t-Butyl 2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (II) may be prepared from 4-((6-((2-(2,4-difluorophenyl)oxiran-2-yl)difluoromethyl)pyridin-3-yl)oxy)benzonitrile (III) as shown in Example 2.

Example 4: Preparation of t-butyl 2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (IV)

[0043] ##STR00011##

[0044] To a slurry of 4-((6-((2-(2,4-difluorophenyl)oxiran-2-yl)difluoromethyl)pyridin-3-yl)oxy)benzonitrile (V) (5 g, 12.49 mmol) in ethanol (40 mL) was added t-butyl carbazate (4.13 g, 31.2 mmol) and the reaction was heated at 80 C. for 24 h, at which point the starting epoxide (V) was completely consumed. The reaction was allowed to cool to 45 C. and seeded with crystals of product IV causing the reaction to cloud. Additional ethanol (40 mL) was added, and the reaction was cooled to room temperature overnight. The resulting slurry was cooled with an ice bath for 30 min and filtered. The solids were rinsed with ethanol (30 mL) and dried under vacuum providing t-butyl 2-(3-(5-(4-cyanophenoxy)pyridin-2-yl)-2-(2,4-difluorophenyl)-3,3-difluoro-2-hydroxypropyl)hydrazine-1-carboxylate (IV) as a white solid (5.42 g, 9.67 mmol, 77% yield). .sup.1H NMR (400 MHz, CDCl.sub.3) 8.37 (d, J=2.7 Hz, 1H), 7.72-7.64 (m, 2H), 7.55 (td, J=8.8, 6.6 Hz, 1H), 7.48 (d, J=8.6 Hz, 1H), 7.37 (dd, J=8.7, 2.7 Hz, 1H), 7.10-7.02 (m, 2H), 6.77 (dddd, J=20.9, 11.4, 8.6, 2.6 Hz, 2H), 3.83 (d, J=13.7 Hz, 1H), 3.74 (dd, J=13.4, 2.8 Hz, 1H), 1.41 (s, 9H). 19F NMR (376 MHz, CDCl.sub.3) -105.15, -108.68 (d, J=22.1 Hz), -109.24, -110.29. ESIMS m/z 533.1 [(M+H)+].

[0045] The contacting of the compound of Formula V with t-butyl carbazate may be carried out from about 25 C. to about 100 C. or from about 60 C. to about 90 C.

[0046] Solvents for use in this process step may include alcohols such as methanol, ethanol, and isopropanol, as well as aprotic solvents such as THF (tetrahydrofuran), acetonitrile, DMSO (dimethylsulfoxide), DMF (N,N-dimethylformamide), and mixtures of any of these solvents.