(5-chloro-2-fluorophenyl)boronic acid

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

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

Procedure: A vial charged with 5-chloro-2-fluorophenylboronic acid (0.431 g, 2.474 mmol), palladiumtetrakis (0.057 g, 0.049 mmol), potassium carbonate (0.684 g, 4.95 mmol), and 1-(2′-amino-7-bromo-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-oxazole]-3-yloxy)propan-2-one (0.400 g, 0.990 mmol) was treated with 5 mL dioxane followed by 1 mL water. The vial was flushed with argon and was heated to 80° C. for 3 hours. The reaction mixture was diluted with EtOAc (25 mL) and dried over MgSO4. The organic layers were combined and concentrated, and the crude residue was purified by column chromatography yielding 1-(2′-amino-7-(5-chloro-2-fluorophenyl)-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-oxazole]-3-yloxy)propan-2-one. MS m/z=454.0 [M+H]. The vial was flushed with argon The reaction mixture was diluted with EtOAc (25 mL) dried over MgSO4 concentrated the crude residue was purified by column chromatography

Conditions: temp:70.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A vial was charged with (S)-2′-amino-3-(3,6-dihydro-2H-pyran-4-yl)-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-oxazole]-7-yl trifluoromethanesulfonate (0.050 g, 0.103 mmol), 5-chloro-2-fluorophenylboronic acid (0.054 g, 0.310 mmol), and Pd(PPh3)4 (5.97 mg, 5.17 μmol). The vial was purged with Ar (g). Then, DMF (0.517 mL) and potassium carbonate (0.259 mL, 0.517 mmol) (as a 2.0 M aq. solution) were added in sequence. The vial was sealed and stirred at 70° C. for one hour. The reaction was diluted with ethyl acetate and washed with water. The aqueous layer was extracted with ethyl acetate, and the combined organic layers were dried with sodium sulfate, filtered, and concentrated. The material was purified via column chromatography (RediSep 40 g, gradient elution 0-7% MeOH in DCM) to afford (S)-7-(5-chloro-2-fluorophenyl)-3-(3,6-dihydro-2H-pyran-4-yl)-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-oxazol]-2′-amine as a white solid. Found MS: MH+=464. The vial was purged with Ar (g) The vial was sealed washed with water The aqueous layer was extracted with ethyl acetate the combined organic layers were dried with sodium sulfate filtered concentrated The material was purified via column chromatography (RediSep 40 g, gradient elution 0-7% MeOH in DCM)

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

Procedure: A vial was charged with (S)-2′-amino-3-(tetrahydro-2H-pyran-4-yl)-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-oxazole]-7-yl trifluoromethanesulfonate (70.0 mg, 0.144 mmol), 5-chloro-2-fluorophenylboronic acid (75 mg, 0.433 mmol), potassium carbonate (100 mg, 0.721 mmol), and Pd(PPh3)4 (8.33 mg, 7.21 μmol). The vial was flushed with Ar (g), then Dioxane (721 μL) and water (0.3 mL) were added in sequence. The vial was sealed and placed in an 80° C. for 1.5 hours. The mixture was diluted with brine (20 mL) and extracted with EtOAc (2×15 mL). The combined organic extracts were dried over sodium sulfate, filtered, and evaporated. The residue was chromatographed on a 24-g Redi-Sep Gold column with 0-60% of a 90:10:1 mix of DCM/MeOH/NH4OH in DCM to give (S)-7-(5-chloro-2-fluorophenyl)-3-(tetrahydro-2H-pyran-4-yl)-5′H-spiro[chromeno[2,3-b]pyridine-5,4′-oxazol]-2′-amine The vial was flushed with Ar (g) Dioxane (721 μL) and water (0.3 mL) were added in sequence The vial was sealed The mixture was diluted with brine (20 mL) extracted with EtOAc (2×15 mL) The combined organic extracts were dried over sodium sulfate filtered evaporated The residue was chromatographed on a 24-g Redi-Sep Gold column with 0-60% of a 90:10:1 mix of DCM/MeOH/NH4OH in DCM

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

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: (R)-3-[N-(4-Bromobenzyl)-N′-t-butoxycarbonyl-hydrazino]-2-hydroxy-propionic acid methyl ester (1.0 g, 2.5 mmol), 5-chloro-2-fluorophenylboronic acid (865 mg, 4.96 mmol), and K2CO3 (857 mg, 6.2 mmol), were combined in EtOH (30 mL, 500 mmol) and water (8 mL, 400 mmol), followed by the addition of SilicaCat® DPP-Pd (0.28 mmol/g loading; 886 mg, 248 μmol). The mixture was heated at 90° C. until the reaction was complete (2 hours). The precipitate was filtered off, and the filtrate was concentrated and purified (Interchim reverse phase chromatography column; 30-95% MeCN in water with 0.5% TFA). The clean fractions were collected, lyophilized, and combined with 4 M HCl in dioxane (8 mL, 30 mmol) and EtOH (10 mL, 200 mmol). The resulting mixture was stirred at room temperature until the reaction was complete (7 hours). The mixture was concentrated to yield an oil, which was stirred in ether with few drops of EtOH overnight. The precipitate was filtered off and rinsed with ether to yield the title compound (140 mg). (2 hours) The precipitate was filtered off the filtrate was concentrated purified (Interchim reverse phase chromatography column; 30-95% MeCN in water with 0.5% TFA) The clean fractions were collected (7 hours) The mixture was concentrated to yield an oil, which The precipitate was filtered off rinsed with ether

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: (R)-3-[N-(4-Bromobenzyl)-N′-t-butoxycarbonyl-hydrazino]-2-hydroxy-propionic acid methyl ester (1.0 g, 2.5 mmol), 5-chloro-2-fluorophenylboronic acid (865 mg, 4.96 mmol), and K2CO3 (857 mg, 6.2 mmol), were combined in EtOH (30 mL, 500 mmol) and water (8 mL, 400 mmol), followed by the addition of SilicaCat® DPP-Pd (0.28 mmol/g loading; 886 mg, 248 μmol). The mixture was heated at 90° C. until the reaction was complete (2 hours). The precipitate was filtered off, and the filtrate was concentrated and purified (Interchim reverse phase chromatography column; 30-95% MeCN in water with 0.5% TFA). The clean fractions were collected, lyophilized, and combined with 4 M HCl in dioxane (8 mL, 30 mmol) and EtOH (10 mL, 200 mmol). The resulting mixture was stirred at room temperature until the reaction was complete (7 hours). The mixture was concentrated to yield an oil, which was stirred in ether with few drops of EtOH overnight. The precipitate was filtered off and rinsed with ether to yield the title compound (140 mg). (2 hours) The precipitate was filtered off the filtrate was concentrated purified (Interchim reverse phase chromatography column; 30-95% MeCN in water with 0.5% TFA) The clean fractions were collected (7 hours) The mixture was concentrated to yield an oil, which The precipitate was filtered off rinsed with ether

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

Procedure: 3-({(4S,5R)-5-[3,5-bis(trifluoromethyl)phenyl]-4-methyl-2-oxo-1,3-oxazolidin-3-yl}methyl)pyrazin-2-yl trifluoromethanesulfonate (Step D, 80 mg, 0.145 mmol), (5-chloro-2-fluorophenyl)boronic acid (30.3 mg, 0.173 mmol), Cs2CO3 (118 mg, 0.361 mmol), 1,1′-bis(diphenylphosphino) ferrocene-palladium dichloride dichloromethane adduct (11.81 mg, 0.014 mmol) and 1,4-dioxane (1 mL) were sealed in a microwave vessel and subjected to microwave irradiation at 140° C. for 25 min. LCMS indicated formation of the desired product. The crude mixture was diluted with MeCN and filtered. The filtrate was purified by preparative HPLC (Kromasil 100-5C 18, 100×21.1 mm) eluting with MeCN/water+0.1% TFA (10% to 100% organic in 10 min, hold 100% in 2 min, 20 mL/min). Related fractions were pooled and evaporated in vacuo to afford an aqueous mixture. The resulting aqueous mixture was extracted with EtOAc, washed with aqueous NaHCO3, dried (Na2SO4), filtered and concentrated to afford a brown glass as the titled compound. LCMS calc.=533.07; found=534.19 (M+H)+. irradiation at 140° C. for 25 min

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: (R)-3-[N-(4-Bromobenzyl)-N′-t-butoxycarbonylhydrazino]-2-hydroxypropionic acid methyl ester (1.0 g, 2.5 mmol), 5-chloro-2-fluorophenylboronic acid (865 mg, 5.0 mmol), and K2CO3 (857 mg, 6.2 mmol), were combined in EtOH (30 mL, 500 mmol) and water (8 mL, 400 mmol), followed by the addition of SilicaCat® DPP-Pd (0.28 mmol/g loading; 886 mg, 248 μmol). The mixture was heated at 90° C. until the reaction was complete (2 hours). The precipitate was filtered off, and the filtrate was concentrated and purified by reverse phase chromatography (30-95% MeCN in water with 0.5% TFA). The clean fractions were collected, lyophilized, and combined with 4 M HCl in dioxane (8 mL, 30 mmol) and EtOH (10 mL, 200 mmol). The resulting mixture was stirred at room temperature until the reaction was complete (7 hours). The mixture was concentrated to yield an oil, which was stirred in ether with few drops of EtOH overnight. The precipitate was filtered off and rinsed with ether to yield the title compound (140 mg). (2 hours) The precipitate was filtered off the filtrate was concentrated purified by reverse phase chromatography (30-95% MeCN in water with 0.5% TFA) The clean fractions were collected (7 hours) The mixture was concentrated to yield an oil, which The precipitate was filtered off rinsed with ether

Conditions: temp:90.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: (R)-3-[N-(4-Bromobenzyl)-N′-t-butoxycarbonylhydrazino]-2-hydroxypropionic acid methyl ester (1.0 g, 2.5 mmol), 5-chloro-2-fluorophenylboronic acid (865 mg, 5.0 mmol), and K2CO3 (857 mg, 6.2 mmol), were combined in EtOH (30 mL, 500 mmol) and water (8 mL, 400 mmol), followed by the addition of SilicaCat® DPP-Pd (0.28 mmol/g loading; 886 mg, 248 μmol). The mixture was heated at 90° C. until the reaction was complete (2 hours). The precipitate was filtered off, and the filtrate was concentrated and purified by reverse phase chromatography (30-95% MeCN in water with 0.5% TFA). The clean fractions were collected, lyophilized, and combined with 4 M HCl in dioxane (8 mL, 30 mmol) and EtOH (10 mL, 200 mmol). The resulting mixture was stirred at room temperature until the reaction was complete (7 hours). The mixture was concentrated to yield an oil, which was stirred in ether with few drops of EtOH overnight. The precipitate was filtered off and rinsed with ether to yield the title compound (140 mg). (2 hours) The precipitate was filtered off the filtrate was concentrated purified by reverse phase chromatography (30-95% MeCN in water with 0.5% TFA) The clean fractions were collected (7 hours) The mixture was concentrated to yield an oil, which The precipitate was filtered off rinsed with ether

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

Procedure: Following the procedure of Intermediate 104, replacing 2,6-difluoro-4-methoxyphenylboronic acid with (5-chloro-2-fluorophenyl)boronic acid gave the title compound.

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

Procedure: (2R,4R)-5-(4-Bromophenyl)-2-hydroxy-4-[(1-hydroxy-1H-1,2,3-triazole-4-carbonyl)amino]pentanoic acid ethyl ester (30 mg, 70 μmol) was combined with 5-chloro-2-fluorophenylboronic acid (22 mg, 126 μmol), K2CO3 (29.1 mg, 211 μmol), EtOH (0.8 mL, 10 mmol), and water (0.2 mL, 10 mmol). SilicaCat DPP-Pd (0.28 mmol/g loading; 25.1 mg, 7.0 μmol) was added the last. The resulting mixture was microwaved at 100° C. for 10 minutes. 1 M LiOH in water (281 μL, 281 μmol) was added, and the resulting mixture was stirred for 1 hour. The mixture was filtered, concentrated, and purified by preparative HPLC to yield the title compound (17 mg). MS m/z [M+H]+ calc'd for C20H18ClFN4O5, 449.10. found 449.2. The resulting mixture was microwaved at 100° C. for 10 minutes The mixture was filtered concentrated purified by preparative HPLC