[Cl:1][C:2]1[CH:7]=[C:6]([C:8]#[CH:9])[CH:5]=[C:4]([Cl:10])[CH:3]=1.C([Li])CCC.CON(C)[C:19]([C:21]1[CH:22]=[N:23][C:24]2[C:29]([CH:30]=1)=[CH:28][CH:27]=[CH:26][CH:25]=2)=[O:20]>C1COCC1>[Cl:1][C:2]1[CH:7]=[C:6]([C:8]#[C:9][C:19]([C:21]2[CH:22]=[N:23][C:24]3[C:29]([CH:30]=2)=[CH:28][CH:27]=[CH:26][CH:25]=3)=[O:20])[CH:5]=[C:4]([Cl:10])[CH:3]=1To a solution of the 1,3-dichloro-5-ethynylbenzene (200 mg, 1.16 mmol) in anhydrous THF cooled to −78° C. under a N2 atmosphere was added nButLi (800 μL, 1.28 mmol). After 5 minutes a solution of the intermediate from step A (380 mg, 1.75 mmol) in THF (3 mL) was added. The reaction was gradually warmed to room temperature over 30 minutes and quenched with saturated NH4Cl solution. The resulting bi-phasic mixture was extracted with ethyl acetate, washed with saturated NaCl solution, dried over anhydrous Na2SO4, filtered and concentrated in vacuo. The residue was purified by flash chromatography using 15% ethyl acetate-hexanes to afford the product as a light yellow solid. 1H NMR (CDCl3, 500 MHz): 9.63 (s, J=2.1 Hz, 1H), 8.96 (d, J=1.6 Hz, 1H), 8.24 (d, J=8.5 Hz, 1H), 8.07 (d, J=8.3 Hz, 1H), 7.94 (t, J=8.0 Hz, 1H), 7.73 (t, J=7.8 Hz, 1H), 7.64 (d, J=1.8 Hz, 2H), 7.55 (t, J=2.0 Hz, 1H). LC-MS: 3.99 min; (M+H)=326.0.
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