Step 1: Synthesis of cyclopropyl-1-ol
Cyclopropylboronic acid (10 g, 0.116 mol) and aqueous sodium hydroxide (8.37 g, 0.209 mol, dissolved in 100 mL of water) were added to a 1 L reaction flask. Under the cooling of an ice bath, 34% hydrogen peroxide (80 mL) was slowly added dropwise, keeping the reaction temperature not higher than 5 °C. After the dropwise addition, the reaction mixture was continued to be stirred at 5°C for 1 hour. Upon completion of the reaction, saturated aqueous sodium thiosulfate solution was added slowly and dropwise to quench the reaction until the potassium iodide-starch test paper no longer showed color. The reaction solution was extracted with ether three times, the organic phases were combined, washed with saturated brine, dried with anhydrous desiccant, filtered and concentrated under reduced pressure at 0 °C to give cyclopropan-1-ol (colorless oil, 4 g, 60% yield). The product did not need further purification and could be used directly in the subsequent reaction. (MS detection: [M+1] not observed)
