[C:1]1([CH3:11])[CH:6]=[C:5](C)[CH:4]=[C:3](C)[C:2]=1[Mg]Br.[C:12]1(=O)[CH2:18][CH2:17]C[CH2:15][CH2:14][CH2:13]1.P(Cl)(OC1C=CC=CC=1)(OC1C=CC=CC=1)=O.C1([Mg]Cl)C=CC=CC=1.Cl>C1COCC1.Cl[Pd](Cl)([P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1)[P](C1C=CC=CC=1)(C1C=CC=CC=1)C1C=CC=CC=1.CCCCC>[C:1]1([C:11]2[CH2:15][CH2:14][CH2:13][CH2:12][CH2:18][CH:17]=2)[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=1Mesitylmagnesium bromide (18.0 mL, 18.0 mmol, 1.0 M in THF) was added over 15 minutes to a solution of cycloheptanone (2.0 g, 17.8 mmol) and diphenyl chlorophosphate (1.1 eq.) in THF (5 mL) at 0° C. The solution was stirred at 0° C. for 30 min, whereafter the solution was allowed to reach room temperature. After stirring the solution for 30 min, dichlorobis(triphenylphosphine)palladium (126 mg, 1 mol %) was added and the solution was warmed to 65° C. Phenylmagnesium chloride (10.8 mL, 1.2 equivalents in THF) was added over 10 minutes, resulting in a gentle reflux of the solvent. After stirring at 65° C. for 30 minutes, the mixture was cooled to rt and poured into a mixture of 3 N HCl (30 mL) and pentane (30 mL). The phases were separated, and the aqueous portion was extracted with pentane (30 mL). The combined organic phase was washed sequentially with 3 N HCl (20 mL), 3 M NaOH (2×20 mL), and brine (20 mL), and dried over MgSO4. Evaporation of the solvent followed by distillation using a Kugelrohr apparatus (oven temperature 100-140° C., 0.065 torr) yielded 1-phenylcycloheptene (1.29 g, 43%).
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