BrCCBr.Cl[Si](C)(C)C.I[CH:11]1[CH2:20][CH2:19][C:14]2([O:18][CH2:17][CH2:16][O:15]2)[CH2:13][CH2:12]1.[F:21][C:22]1[C:27](I)=[N:26][CH:25]=[CH:24][N:23]=1>CC(N(C)C)=O.[Zn].[Cu]I>[F:21][C:22]1[C:27]([CH:11]2[CH2:20][CH2:19][C:14]3([O:18][CH2:17][CH2:16][O:15]3)[CH2:13][CH2:12]2)=[N:26][CH:25]=[CH:24][N:23]=1To a suspension of activated zinc dust (51 g, 0.78 mol, 1.94 eq.) in anhydrous DMA (100 mL) was added 1,2-dibromoethane (5.5 mL, 0.064 mol, 0.16 eq.), followed by the slow addition of chlorotrimethylsilane (8.1 mL, 0.064 mol, 0.16 eq.) over 5 min. The resulting mixture was stirred for 15 min under nitrogen. Then a solution of 8-iodo-1,4-dioxaspiro[4.5]decane (172 g, 0.639 mol, 1.59 eq.) in anhydrous DMA (300 mL) was added to the above suspension over 30 min keeping the internal temperature below 65° C. The resulting mixture was stirred for 1 hour and cooled to room temperature. The prepared zinc reagent was allowed to stand and the upper clear solution was transferred to a degassed and well stirred solution of 2-fluoro-3-iodopyrazine (see PREPARATION P6.2; 90 g, 0.402 mol, 1.0 eq.), PdCl2(dppf)CH2Cl2 (9.8 g, 0.012 mol, 0.03 eq.), and CuI (4.75 g, 0.025 mol, 0.062 eq.) in anhydrous DMA (300 mL) using a cannula. DMA (100 mL) was used to rinse the remaining zinc dust and the solution was added to the above mixture. The resulting mixture was heated to 80° C. under nitrogen and stirred overnight.
Wird geladen…
