丙酮+HCN ====(CH3)2C(OH)CN ===脱水===(CH2=C(CH3)CN ===水解==CH2=C(CH3)COOH+SOCl2 ==CH2=C(CH3)COCl +HOCH3 ===产物α-甲基丙烯酸甲酯丙二酸二乙酯+氯苯=碱性条件===苄基丙二酸二乙酯===水解===3-苯基丙酸
