[C:1]([O:4][CH2:5][C:6]([CH2:8][Si](C)(C)C)=[CH2:7])(=O)[CH3:2].[C:13](OCC)(=O)[CH:14]=[CH2:15].P(OC(C)C)(OC(C)C)[O:21]C(C)C>C1(C)C=CC=CC=1.C([O-])(=O)C.[Pd+2].C([O-])(=O)C>[CH2:13]=[C:14]1[CH2:15][CH2:8][CH:6]([C:5]([O:4][CH2:1][CH3:2])=[O:21])[CH2:7]1
The following reaction was performed in a 15 mL sealed tube, behind a safety shield. To 2-((trimethylsilyl)methyl)allyl acetate (2.227 mL, 10.73 mmol) in toluene (2 mL) was sequentially added ethyl acrylate (2.92 mL, 26.8 mmol), triisopropyl phosphite (1.474 mL, 6.44 mmol) and palladium(II)acetate (0.241 g, 1.073 mmol). The contents were purged with nitrogen gas for 5 min. and heated at 100° C. for 45 h. The reaction mixture was cooled to RT and concentrated under reduced pressure. The liquid was transferred to a 50 mL round bottom flask and distilled using a high vacuum pump. Fractions distilling at 50° C. were collected and concentrated to yield 1.317 g (80%) of ethyl 3-methylenecyclopentanecarboxylate. 1H NMR (400 MHz, CDCl3) δ ppm 4.90-4.85 (m, 2H), 4.14 (q, 2H, J=7.0 Hz), 2.87-2.78 (m, 1H), 2.61-2.53 (m, 2H), 2.51-2.23 (m, 2H), 2.09-1.82 (m, 2H), 1.29-1.23 (t, 3H, J=7.2 Hz).
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