摘要
以对氟苯甲腈,氨基甲酸铵为原料,N-乙酰半胱氨酸为催化剂,合成了对氟苯甲脒。考察了催化剂的用量、温度、原料配比和时间对产率的影响优化条件为:n(对氟苯甲腈):n(N-乙酰半胱氨酸):n(氨基甲酸铵)=1:1:0.55,加成反应的反应温度为50℃,反应时间为20h;胺化反应的反应温度为50℃,反应时间为24h。对氟苯甲脒产率达到92%。反应条件温和,周期短,无污染。
N-Acetyl-L-cysteine was used as a catalyst for the reaction of 4-fluorobenzonit(?)ile with ammonium carbamate.4-Fluorobenzamidinebydrochloride was obtained in 92%yield under the optimum reaction conditions:n(4- fluorobenzonitrile):n(N-aceryl-L-cysteine):n(ammoniuin carbamate)=1:1:0.55.cycloaddition reaction temperature is 50(?) and the reaction time is 8h,aminating reaction temperature is 50℃and the reaction lime is 24h.The reaction conditions is mild,its cycle is short and it is no polluting.