Reaction of hept-1-ene with EtMgCl in THF in the presence of TaCl5-(i-OPr)3P catalyst [EtMgCl-hept-1-ene-TaCl5-(i-OPr)3P, 24:20:1]; TaCl5-(i-OPr)3P, 1:1; EtMgCl in THF at a concentration of 0.5 mM; 20 °C; at room temperature The reaction was carried out at room temperature for 3 h to form organomagnesium compound 2. The procedure was as follows: to a solution of EtMgCl (12 mmol) in THF (24 mL) was added hept-1-ene (10 mmol, 1.4 mL), TaCl5 (0.2 g, 0.5 mmol) and (i-OPr)3P (0.1 g, 0.5 mmol). CO2 was slowly passed into the resulting mixture for 3 h at 0°C. After completion of the reaction, the mixture was treated with 10% HCl solution (15 mL) to afford carboxylic acid 3 (1.7 g, 97%, boiling point 272 °C, 750 mmHg). The product was analyzed by IR spectroscopy (1710 cm-1 ), PMR spectroscopy (0.88-0.92 ppm, 2H, m; 1.16-1.52 ppm, 10H, m; 1.56-1.80 ppm, 1H, m; 2.28-2.38 ppm, 2H, m; 11.40 ppm, 1H, s), and 13C NMR spectroscopy (14.03, 19.75, 23.19, 28.30, 31.83, 31.97, 32.27, 33.10, 37.10, 179.37 ppm) for characterization. Finally, the reaction mixture was extracted with Et2O (3 × 50 mL) and the extract was dried with anhydrous MgSO4 and evaporated.
