反应详情

A 1 liter 3 neck round bottomed flask was charged with 600 ml of heptane, 155.3 g of 2-(2,2,3-trimethylcyclopent-3-en-1-yl)-2,4-dimethyl-4-pentenol at 97.7% (0.68 mole) and 0.9 g of p-TSA. The batch was refluxed under nitrogen for 26 hours. Then batch was cooled and washed with 500 ml of 10% sodium carbonate, 500 ml of water and 500 ml of brine. The batch was dried with magnesium sulfate, filtered, and concentrated in vacuo to afford 163.3 g of crude product. Distillation of the product afforded 150.3 g of purified product (92.7%). BP 84° C./0.5 mmHg; 1H-NMR (300 MHz), δ 0.92 (3H, s), 1.10 (3H, s), 1.20 (3H, s), 1.25 (3H, s), 1.33 (3H, s), 1.55 (4H, sharp m), 1.81-1.99 (2H, m), 2.16 (2H, br m), 3.60 (2H, AB quintet J=8.7 Hz), 5.24 (1H, s); 13C-NMR (75 MHz), δ 12.35, 22.03, 24.57, 25.66, 28.69, 29.96, 32.48, 47.38, 48.36, 50.58, 57.22, 77.63, 80.60, 121.20, 148.01; IR (Neat), 3020, 2980, 1450, 1060 cm-1 ; MS (m/e), 222 (M+), 207, 191, 95, 43;

1. temperatureThe batch was refluxed under nitrogen for 26 hours
2. temperatureThen batch was cooled
3. washwashed with 500 ml of 10% sodium carbonate, 500 ml of water and 500 ml of brine
4. dry with materialThe batch was dried with magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customto afford 163.3 g of crude product
8. distillationDistillation of the product