[C:1]([C:3]1[C:8](=[O:9])[NH:7][C:6]([CH3:16])([C:10](N(OC)C)=[O:11])[CH2:5][C:4]=1[C:17]1[CH:22]=[CH:21][C:20]([CH3:23])=[CH:19][CH:18]=1)#[N:2].[C:24]([Mg]Br)#[CH:25]>O1CCCC1>[CH3:16][C:6]1([C:10](=[O:11])[C:24]#[CH:25])[NH:7][C:8](=[O:9])[C:3]([C:1]#[N:2])=[C:4]([C:17]2[CH:18]=[CH:19][C:20]([CH3:23])=[CH:21][CH:22]=2)[CH2:5]1Intermediate 109A (0.0887 g, 0.283 mmol) was dissolved in tetrahydrofuran (1 mL) in a 25 mL 1 neck pear shaped flask that was equipped with a magnetic stirrer and an Ar inlet. Ethynylmagnesium bromide (5.66 mL, 2.83 mmol) was added dropwise and the reaction mixture was stirred at 35° C. for 4 h. The reaction mixture was cooled to rt, quenched with sat'd. aq NH4Cl (5 mL) and extracted with EtOAc (2×10 mL). The organic phases were combined and concentrated in vacuo. The residue was purified by silica gel chromatography (24 g silica gel, eluted with 0-100% EtOAc in hexanes) to give the desired product (0.06 g, 78%) as an orange solid. LCMS Anal. Calc'd for C12H14N2O2 278.1, found [M+H] 279.0.
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