Reaction Steps
To a solution of oct-1-yne (56.2 mg, 0.5 mmol) and Cp2ZrCl2 (206.7 mg, 1.4 mmol, 1.4 eq.) in THF (2.5 mL) at RT was rapidly added a 1 M THF solution of LiAlH(Ot-Bu)3 (0.7 mL, 1.4 mmol, 1.4 eq.). A resulting dark red solution was stirred at RT for 15 min. At that time, dry ZnBr2 (157.7 mg, 1.4 mmol, 1.4 eq., Aldrich) and THF (1 mL) were added at RT. After 30 min., 1-iodo-4-methoxybenzene (165.5 mg, 1.4 mmol, 1.4 eq., Aldrich), Pd(PPh3)4 (11.6 mg, 0.001 mmol, 0.02 eq.) and DMF (1 mL) were added. The resultant mixture was stirred at RT for 5 h and then quenched with 1 N HCl, and extracted with EtOAc (4×5 mL). Organic extracts were combined and washed with H2O and brine, dried over MgSO4 and concentrated via evaporation under reduced pressure. Purification of the residue was performed using a silica gel column (silica gel 60, 230-400 mesh) with CH2Cl2/hexanes as eluent. (E)-1-iodooct-1-ene (41.3 mg, 38% yield) was obtained as a colorless oil. 1H NMR (400 MHz, CDCl3) δ ppm: 7.27 (d, J=8.62 Hz, 21-1), 6.83 (d, J=8.64 Hz, 2H), 6.31 (d, J=15.79 Hz, 1H), 6.08 (dt, J=14.23, 6.89 Hz, 1H), 3.79 (s, 3H), 2.17 (td, J=7.14, 7.07 Hz, 2H), 1.50-1.40 (m, 2H), 1.38-1.27 (m, 6H), 0.89 (t, J=6.31 Hz, 3H) 13C NMR (101 MHz, CDCl3) δ ppm: 158.59, 130.84, 129.09, 128.99, 126.93 (2C), 113.89 (2C), 55.27, 33.02, 31.77, 29.50, 28.91, 22.63, 14.09. Physical and spectral data were consistent with those previously reported (see Nakao, Y.; Imanaka, H.; Sahoo, A. K.; Yada, A.; Hiyama, T. J. Am. Chem. Soc. 2005, 127, 6952-6953.)
