Br[C:2]1[CH:3]=[C:4]([CH2:8][C:9]([P:21](=[O:30])([O:26][CH:27]([CH3:29])[CH3:28])[O:22][CH:23]([CH3:25])[CH3:24])([P:11](=[O:20])([O:16][CH:17]([CH3:19])[CH3:18])[O:12][CH:13]([CH3:15])[CH3:14])[F:10])[CH:5]=[N:6][CH:7]=1.[CH3:31][C:32]1[C:36](B(O)O)=[C:35]([CH3:40])[O:34][N:33]=1.C(=O)([O-])[O-].[K+].[K+]>COCCOC>[CH3:31][C:32]1[C:36]([C:2]2[CH:3]=[C:4]([CH2:8][C:9]([P:21](=[O:30])([O:22][CH:23]([CH3:24])[CH3:25])[O:26][CH:27]([CH3:29])[CH3:28])([P:11](=[O:20])([O:16][CH:17]([CH3:18])[CH3:19])[O:12][CH:13]([CH3:15])[CH3:14])[F:10])[CH:5]=[N:6][CH:7]=2)=[C:35]([CH3:40])[O:34][N:33]=1A sample of tetraisopropyl (2-(5-bromopyridin-3-yl)-1-fluoroethane-1,1-diyl)bis(phosphonate) (85 mg; 0.16 mmol), Pd(Ph3)4 (36.9 mg; 0.032 mmol) and (3,5-dimethylisoxazol-4-yl)boronic acid (34 mg; 0.24 mmol) are added in a vial, the vial is capped with a septum and added DME (4 mL) is added. The mixture is immediately flushed with argon, potassium carbonate solution (2.5 eq.) is added and flushed again with argon. The reaction mixture is stirred at 80° C. for 36 h under argon. The mixture is cooled, diluted with EtOAc and filtered through Celite™, the Celite™ is rinsed 3× with EtOAc/MeOH (1:1). The combined filtrate is concentrated under vacuum and deposited on silica gel. Purification by column chromatography on silica gel (pre washed with 1% NEt3 in hexanes) using a solvent gradient from hexanes to EtOAc, and then to 50% MeOH in EtOAc lead to the isolation of the product as a brown oil (41 mg; 47% yield).
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