C(=O)=O.C[C:5]([CH3:7])=O.[C:8]([O:11][CH2:12][C:13]1[C:18](Br)=[CH:17][CH:16]=[CH:15][C:14]=1Br)(=[O:10])[CH3:9].[Zn](CC)[CH2:22][CH3:23].Cl>C1COCC1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.C1C=CC(P(C2C=CC=CC=2)[C-]2C=CC=C2)=CC=1.Cl[Pd]Cl.[Fe+2].CCOC(C)=O.CCCCCCC>[C:8]([O:11][CH2:12][C:13]1[C:18]([CH2:22][CH3:23])=[CH:17][CH:16]=[CH:15][C:14]=1[CH2:5][CH3:7])(=[O:10])[CH3:9]To a cooled (dry ice-acetone bath) mixture of 2,6-dibromo-benzyl acetate (5.05 g, 16.4 mmol) and PdCl2(dppf) (0.08 eq) in dry THF (50 mL) was added 1.1 M Et2Zn (60 mL, 66 mmol, 4 eq). The resulting mixture was allowed to warm to RT, stirred at 45° C. (programmed block temperature, ˜40 h), and added to a stirred mixture of dilute HCl and heptane/EtOAc. The organic layer was dried (Na2SO4), filtered, and evaporated. Chromatography (2%-10% EtOAc/heptane stepwise gradient) gave 2.12 g (yield of 63%) of the title product, along with 0.20 g of 2,6-diethylbenzyl alcohol. 1H NMR (300 MHz, CDCl3) δ 1.21 (t, 6H), 2.07 (s, 3H), 2.70 (q, 4H), 5.19 (s, 2H), 7.09 (d, 2H), 7.22 (dd, 1H). The following compound was prepared by making appropriate substitutions to the above procedure:
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