5-Methyl-,chloro,and bromo-substituted 2-hydroxy-acetophenones(2a-c) were synthesized in good yields of 77. 3%-80. 4%,involving the acetylation reaction of the respective 4-methyl-,chloro,and bromo-phenols(1a-c) with acetic anhydride fol-lowed by Fries rearrangement in the presence of BF3·2HAc as catalyst under solvent-free condition. 3,5-Dihalo-substituted 2-hy-droxy-acetophenones(4a-c)were obtained in the yields of 61. 8-92. 4%by the halogenation reaction of 2-hydroxy-acetophenone(3) with N-halosuccinimide using PEG-400 as solvent at room temperature. The nitration of 2-hydroxy-acetophenone(3)with a green ni-trating agent of cerium ammonium nitrate( CAN) was also investigated,affording two products 3-nitro-and 5-nitro-substituted 2-hy-droxy-acetophenones(5a,b)in 29. 8% and 63. 9%yield,respectively. Our developed experimental procedures for the preparation of the 2-hydroxy-acetophenone derivatives 2a-c,4a-c,and 5a,b are characterized by mild conditions,simple work-up,and environmen-tal benefits of the reaction medium,and thus could be used as a useful and green alternative approach to previously reported meth-ods.%以对甲(氯、溴)苯酚(1a-c)为起始原料经酰化得对甲(氯、溴)苯酚乙酯,再以BF3·2HAc为催化剂无溶剂条件下实现Fries重排,以77．3%-80．4%的收率分别得到了5-甲基(氯、溴)邻羟基苯乙酮(2a-c)；应用环境友好的聚乙二醇-400为溶剂, N-氯(溴、碘)代丁二酰亚胺为卤代试剂对邻羟基苯乙酮进行卤代反应,以61．8%-92．4%的收率制备3,5-二氯(溴、碘)邻羟基苯乙酮(4a-c)；以邻羟基苯乙酮为原料,硝酸铈铵( CAN)为绿色硝化试剂,分别以29．8%和63．9%的收率得到了3位和5位硝化产物1-(2-羟基-3-硝基苯基)乙酮、1-(2-羟基-5-硝基苯基)乙酮(5a-b)。以上制备过程具有反应条件温和、后处理简单、环境友好等优点,为制备取代邻羟基苯乙酮提供了简单且绿色的新方法。
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