ethenylboronic acid

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:

Conditions: temp:-78.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Compound 5b (2.0 g, 8.0 mmol) in THF (30 mL) was cooled to −78° C. and tert-butyllithium (9.9 mL, 16.8 mmol) as 1.7 M solution in pentane was added slowly. After stirring at −78° C. for 30 min, dibutyl ester of vinyl boronic acid was added dropwise. The mixture was stirred at −78° C. for 1 h, then was warmed up to room temperature and stirred overnight. Concentrated HCl (4 mL) was added and was stirred at room temperature for 4 h. Water (10 mL) was added and THF was removed under reduced pressure. The residue was extracted with ethyl ether, washed with brine, dried over magnesium sulfate, and concentrated under reduced pressure. The crude product was purified by flash column chromatography (9:1 hexane/ethyl acetate) to give 11 (383 mg, 30%) as a yellowish oil; 1H NMR (300 MHz, DMSO-d6) δ (ppm) 5.27 (s, 2H), 6.25 (t, J=8.5 Hz, 1H), 6.50 (d, J=9.4 Hz, 2H), 7.06-7.15 (m, 2H), 7.89 (dd, J=5.6, 7.9 Hz, 1H); ESI-MS m/z (M+H)+; HPLC purity: 98.7%; Anal. (C9H8BFO 0.1H2O)C, H. The mixture was stirred at −78° C. for 1 h was warmed up to room temperature stirred overnight was stirred at room temperature for 4 h THF was removed under reduced pressure The residue was extracted with ethyl ether washed with brine dried over magnesium sulfate concentrated under reduced pressure The crude product was purified by flash column chromatography (9:1 hexane/ethyl acetate)

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

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

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

Procedure: A scintillation vial equipped with a stirbar was charged with (S)-6-bromo-1-(1-phenylethyl)-1H-imidazo[4,5-b]pyrazin-2-ol (1.0 equiv), vinyl boronic acid (2.2 equiv), and (DPPF)PdCl2 (0.10 equiv). The vial was fitted with a septum-lined cap and purged with nitrogen for 5-10 min. To this mixture was added dioxane (16.6 volume equivalents) and degassed 2N K2CO3 (4.2 volume equivalents) by syringe. The resulting mixture was heated to 90° C. overnight. The mixture was cooled to room temperature, diluted with 12 volume equivalents EtOAc, washed with twice with saturated aq. NaHCO3, and once with brine. The organic layer was dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Biotage MPLC 5%-40% EtOAc/Hexanes) provided the title compound as an off-white solid (54%). LCMS m/z (APCI)=267.0 (M+H). A scintillation vial equipped with a stirbar The vial was fitted with a septum-lined cap purged with nitrogen for 5-10 min To this mixture was added dioxane (16.6 volume equivalents) degassed 2N K2CO3 (4.2 volume equivalents) by syringe The mixture was cooled to room temperature diluted with 12 volume equivalents EtOAc washed with twice with saturated aq. NaHCO3 The organic layer was dried over sodium sulfate filtered concentrated in vacuo

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

Procedure: To a microwave vessel was added 3-bromo-6-(6-methyl-[1,2,4]triazolo[4,3-b]pyridazin-3-ylmethyl)-quinoline (500 mg, 1.41 mmol, 1 equiv), vinyl boronic acid (299 uL, 1.76 mmol, 1.25 equiv), K2CO3 (390 mg, 2.82 mmol, 2.0 equiv) followed by 1,4-dioxane (10 mL) and water (5 mL). The solution was degassed with nitrogen for 10 min and then dichloro[1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloromethane adduct (51 mg, 0.07 mmol, 0.05 equiv) was added. The microwave vessel was capped and reacted in a microwave reactor at 130° C. for 30 min. The microwave vessel was cooled and then the mixture was extracted into dichloromethane and washed with water. The volatiles were removed in vacuo and the residue absorbed onto silica gel and purified by flash chromatography (SiO2, CH2Cl2:CH3OH 100:0-80:20) to obtain the title compound as a brown oil (35% yield). Analytical data presented in Table 1. The solution was degassed with nitrogen for 10 min The microwave vessel was capped reacted in a microwave reactor at 130° C. for 30 min The microwave vessel was cooled the mixture was extracted into dichloromethane washed with water The volatiles were removed in vacuo the residue absorbed onto silica gel purified by flash chromatography (SiO2, CH2Cl2:CH3OH 100:0-80:20)

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

Procedure: A mixture of 3,6-dichloropyridazine (6 g, 40.3 mmol), vinyl boronic acid pinnacol ester (6.21 g, 6.83 mL, 40.3 mmol), potassium carbonate (120 mmol, 16.7 g), 1,4-dioxane (60 mL) and water (24 mL) was degassed for 15 min with nitrogen gas. Dichloro[1,1′-bis(diphenylphosphino)ferrocene]palladium(II) dichloromethane adduct (0.4 mmol, 292 mg) was then added and the mixture heated to 80° C. for 4 hours. The aqueous phase was then removed via pipette and the organic phase concentrated onto silica gel and purified via flash column chromatography (SiO2, hexane:ethyl acetate 100:0-60:40) to return the title compound as a white solid (5.2 g, 92% yield). 1H NMR (CDCl3): δ 5.75 (1H, d), 6.25 (1H, d), 7.05 (1H, dd), 7.49 (1H, d), 7.59 (1H, d). MS m/z=141 (M+H+)+. was degassed for 15 min with nitrogen gas The aqueous phase was then removed via pipette the organic phase concentrated onto silica gel purified via flash column chromatography (SiO2, hexane:ethyl acetate 100:0-60:40)

Conditions: temp:120.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a mixture of (S)-tert-butyl ((3-bromopyridin-2-yl)(4-(trifluoromethyl)-phenyl)methyl)carbamate (0.4 g, 0.93 mmol) in water (2 mL) and EtOH (8 mL) were added K3PO4 (0.3 g, 1.3 mmol), vinyl boronic acid (4 mL, 9.3 mmol) and A−taPhos)2PdCl2 (Guram, A. S. et al. Org. Lett. 2006, 8, 1787; 0.13 g, 0.01 mmol). The resulting mixture was stirred at 120° C. for 1 h. Reaction progress was monitored by TLC (20% EtOAc in petroleum ether). After completion of reaction, water (50 mL) was added to the reaction mixture, and the product was extracted with DCM (3×25 mL). The combined organic layers were separated, dried over anhydrous sodium sulfate, and purified by column chromatography using silica (100-200 mesh) and using 15-30% EtOAc in petroleum ether as an eluent. In this manner, (S)-tert-butyl ((4-(trifluoromethyl)phenyl)(3-vinylpyridin-2-yl)methyl)carbamate was obtained as an off-white solid. MS (ESI pos. ion) m/z: 378.9 (M+1). Reaction progress was added to the reaction mixture the product was extracted with DCM (3×25 mL) The combined organic layers were separated dried over anhydrous sodium sulfate purified by column chromatography