An Electron-Deficient Diene as Ligand for Palladium-Catalyzed Cross-Coupling Reactions
FULL PAPERS
Experimental Section
Supporting Information
The characterization data is available in a Supporting Infor-
mation file.
Synthesis of L1
Dicyclopentadiene (5 g) was heated to 180 8C, the cyclopen-
ta-1,3-diene was then distilled out. To this cyclopenta-1,3-
diene (3.3 g, 50 mmol), diethyl but-2-ynedioate (8.5 g,
50 mmol) was added dropwise. The color of the solution
turned to light yellow. The reaction was exothermic. The
product was distilled under vacuum to afford a colorless
liquid; yield:. 10.4 g (88%).
Acknowledgements
This work was support by National Natural Science Founda-
tion of China (20502020) and the startup fund from Wuhan
University.
Synthesis of Catalyst 1
Palladium(II) chloride (1.58 g, 8.94 mmol), ligand L1 (7.4 g,
31.3 mmol), anhydrous sodium acetate (5.87 g, 71 mmol)
and anhydrous methanol (200 mL) were charged into a 500-
mL oven-dried three-necked flask purged with N2. The mix-
ture was heated to reflux and stirred overnight. The solution
was washed with degassed water. The aqueous phase was
extracted with CH2Cl2. The organic phrase was dried with
anhydrous sodium sulfate and the solvent evaporated under
vacuum. Removal of further solvent using an oil pump pro-
vided a black crystalloid material; yield: 6.7 g.
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General Procedure for Negishi Couplings Involving
PrimaryAlkylzinc Reagents (Table 1 and Table 2)
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General Procedure for Negishi Coupling Involving
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Adv. Synth. Catal. 2008, 350, 1349 – 1354
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