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Typical Experimental Procedures.Preparation of Compound 3.
To a solution of 2 (2.120 g, 10 mmol) in dry THF (90 mL) a 0.1 M solution of Li2CuCl4 (5.4 mL, 0.5 mmol) was added dropwise after cooling to 0 °C. Then a solution of BuMgCl (7 mL, 2 M, 14 mmol) was added dropwise over 20 min. The mixture was stirred at 0 °C for 3 h and then at r.t. overnight. Then sat. aq NH4Cl was added and the mixture extracted with EtOAc, dried over MgSO4 and the solvent was removed in vacuo. The residue was purified by SiO2 chromatography (cyclohexane-EtOAc, 97:3) to yield 3 (1520 mg, 72%): colorless oil. 1H NMR (400 MHz, CDCl3): δ = 5.17 (t of app. sext, J = 7.0, 1.1 Hz, 1 H), 2.69 (t, J = 6.3 Hz, 1H), 2.04-2.19 (m, 2 H), 1.97 (q, J = 7.0 Hz, 2 H), 1.54-1.70 (m, 2 H), 1.60 (s, 3 H), 1.25-1.36 (m, 6 H), 1.29 (s, 3H), 1.25 (s, 3 H), 0.88 (t, J = 7.1 Hz, 3 H). 13C NMR (100 MHz, CDCl3, DEPT): δ = 133.9, 125.6, 64.3, 58.4, 36.5, 31.7, 29.6, 28.0, 27.6, 25.0, 22.7, 18.9, 16.1, 14.2. IR (film): 2925, 1460, 1375, 1120 cm-1. HRMS (EI): m/z calcd for C14H26O: 210.1984; found: 210.1986.
Preparation of Compound 14.
To a vigorously stirred suspension of Mg (29 mg, 1.2 mmol) in THF (2 mL) was added 2-bromoanisol (225 mg, 1.2 mmol). The mixture was stirred at reflux until dissolution of the metal and added dropwise to a solution of 2 (85 mg, 0.4 mmol) and Li2CuCl4 (0.20 mL of a 0.1 M solution in THF, 0.02 mmol) in THF (2 mL) at 0 °C. Stirring was continued for 4 h at r.t. After addition of a sat. solution of NH4Cl the mixture was extracted with EtOAc, dried over MgSO4, and the solvent was removed in vacuo. Purification by SiO2 chromatography (cyclohexane-EtOAc, 95:5) yielded 14 (72 mg, 69%): colorless oil. 1H NMR (400 MHz, CDCl3): δ = 7.17 (td, J = 7.7, 1.5 Hz, 1 H), 7.12 (dd, J = 7.4, 1.5 Hz, 1 H), 6.87 (td, J = 7.4, 1.1 Hz, 1 H), 6.77 (br d, 1 H), 5.36 (tq, J = 7.3, 1.2 Hz, 1 H), 3.82 (s, 3 H), 3.34 (d, J = 7.3 Hz, 2 H), 2.70 (t, J = 6.2 Hz, 1 H), 2.31-2.05 (m, 2 H), 1.73 (s, 3 H), 1.71-1.57 (m, 2 H), 1.26 (s, 3 H), 1.24 (s, 3 H). 13C NMR (100 MHz, CDCl3, DEPT): δ = 157.5, 135.1, 130.0, 129.5, 127.1, 123.4, 120.6, 110.4, 64.4, 58.5, 55.5, 36.5, 28.5, 27.6, 25.0, 18.9, 16.2. IR (film): 2970, 2930, 1720, 1600, 1490, 1460, 1380, 1290 cm-1. HRMS (EI): m/z calcd for C17H24O2: 260.1776; found: 260.1782.
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