[CH2:1]([C:3]1[CH:8]=[C:7]([C:9]([O:11][CH3:12])=[O:10])[CH:6]=[CH:5][N+:4]=1[O-])[CH3:2].[CH3:14][N:15](C)C(Cl)=O.C(N(CC)CC)C.C[Si](C#N)(C)C>C(#N)C>[C:14]([C:5]1[CH:6]=[C:7]([CH:8]=[C:3]([CH2:1][CH3:2])[N:4]=1)[C:9]([O:11][CH3:12])=[O:10])#[N:15]Under N2, 2-ethyl-4-(methoxycarbonyl)pyridine 1-oxide (0.165 g, 911 μmol, Eq: 1.00) was dissolved in Acetonitrile (4 ml). Dimethylcarbamylchlorid (108 mg, 92.1 μl, 1.00 mmol, Eq: 1.1), triethylamine (175 mg, 239 μl, 1.73 mmol, Eq: 1.9) and Trimethylsilylcyanid (280 mg, 355 μl, 2.82 mmol, Eq: 3.10) were added and the RM was stirred at 90° C. overnight. The RM became an orange solution. Control with TLC: the reaction was finished. At RT, the RM was partitioned between water and EtOAc. The organic phase was dried over MgSO4; filtered; concentrated in vacuo: 350 mg; NMR: T205185. The crude material was purified by flash chromatography (silica gel, 20 g, 5% to 50% EtOAc in heptane). Light yellow oil.
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