[N+:1]([C:4]1[CH:5]=[CH:6][C:7]([C:10]2[CH:15]=[CH:14][C:13](B3OC(C)(C)C(C)(C)O3)=[CH:12][CH:11]=2)=[N:8][CH:9]=1)([O-:3])=[O:2].C(=O)([O-])[O-].[K+].[K+].FC(F)(F)S(O[C:37]1[CH2:42][CH2:41][C:40]([C:48]([O:50][CH2:51][CH3:52])=[O:49])([C:43]([O:45][CH2:46][CH3:47])=[O:44])[CH2:39][CH:38]=1)(=O)=O>O1CCOCC1.O.C1C=CC([P]([Pd]([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)([P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)[P](C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1>[N+:1]([C:4]1[CH:5]=[CH:6][C:7]([C:10]2[CH:11]=[CH:12][C:13]([C:37]3[CH2:42][CH2:41][C:40]([C:43]([O:45][CH2:46][CH3:47])=[O:44])([C:48]([O:50][CH2:51][CH3:52])=[O:49])[CH2:39][CH:38]=3)=[CH:14][CH:15]=2)=[N:8][CH:9]=1)([O-:3])=[O:2]A flask was charged with 5-nitro-2-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)pyridine (3.9 g, 10.73 mmol) and potassium carbonate (6.77 g, 48.3 mmol) in dioxane (60 ml) and Water (25 ml), and stirred at room temperature for 10 minutes under nitrogen. Then Pd(PPh3)4 (1.240 g, 1.073 mmol) and diethyl 4-(((trifluoromethyl)sulfonyl)oxy)cyclohex-3-ene-1,1-dicarboxylate (4.22 g, 11.27 mmol) were added to the reaction mixture. The flask was sealed, flushed with nitrogen for three times and heated at 100° C. for 1 hour. The organic solvent was evaporated under vacuum and EtOAc (3×100 ml) was used to extract and the combined organic solvent was washed by saturated aqueous sodium bicarbonate solution, brine, and dried over Na2SO4, then concentrated. The residue was purified by flash chromatography (heptanes/acetone 1/2) to afford diethyl 4′-(5-nitropyridin-2-yl)-5,6-dihydro-[1,1′-biphenyl]-4,4(3H)-dicarboxylate (2.8 g, 61%) as yellow solid. 1H NMR (400 MHz, METHANOL-d4) δ ppm 1.25 (t, J=7.20 Hz, 6H) 2.30 (dt, J=6.28, 3.24 Hz, 2H) 2.53 (dd, J=4.67, 1.77 Hz, 2H) 2.76 (dd, J=3.98, 2.08 Hz, 2H) 4.20 (q, J=7.20 Hz, 4H) 6.19 (s, 1H) 7.06-8.88 (m, 7H).
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