[CH2:1]=[C:2]1[CH2:7][CH2:6][N:5]([C:8]([O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:9])[CH2:4][CH2:3]1.C12BC(CCC1)CCC2.C1COCC1.[Cl:29][C:30]1[N:31]=[N:32][C:33](Cl)=[CH:34][CH:35]=1.C([O-])([O-])=O.[K+].[K+]>O1CCOCC1.O.CCOC(C)=O>[Cl:29][C:30]1[N:31]=[N:32][C:33]([CH2:1][CH:2]2[CH2:7][CH2:6][N:5]([C:8]([O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:9])[CH2:4][CH2:3]2)=[CH:34][CH:35]=1To a flask containing tert-butyl 4-methylenepiperidine-1-carboxylate (487 mg, 2.47 mmol) was added 0.5 M 9-borabicyclo[3.3.1]nonane in THF (5.4 mL, 2.72 mmol). The reaction was refluxed at 65° C. for 1 h then added to a degassed suspension of 3,6-dichloropyridazine (368 mg, 2.47 mmol), K2CO3 (1.0 g, 7.41 mmol), and PdCl2(dppf)CH2Cl2 (101 mg, 0.12 mmol) in 1,4-dioxane (5.2 mL) and water (0.88 mL). The resulting reaction mixture was heated at 60° C. for 3 h then cooled to RT and diluted with EtOAc. The suspension was filtered through celite and concentrated in vacuo. Silica gel chromatography, eluting with 0-100% EtOAc/heptane, afforded the product, tert-butyl 4-((6-chloropyridazin-3-yl)methyl)piperidine-1-carboxylate (376 mg, 1.21 mmol, 49% yield). 1H NMR (DMSO-d6) δ: 7.85 (d, J=8.8 Hz, 1H), 7.70 (d, J=8.8 Hz, 1H), 3.74-4.05 (m, 2H), 2.85 (d, J=7.3 Hz, 2H), 2.54-2.79 (m, 2H), 1.82-2.01 (m, 1H), 1.48-1.62 (m, 2H), 1.38 (s, 9H), 0.97-1.18 (m, 2H).
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