Irradiation of o-alkenylphenols with alkylamines resulted in Markovnikov-type amination to give o-(1-alkylaminoalkyl)phenols in relatively good yields. The photoamination was initiated by a proton transfer from the ammonium ion to the alkenyl group of o-alkenylphenolate anion in the excited state in the ion pair formed between the phenols and the amines. The resulting zwitter ion allowed the nucleophilic addition of the amine at the benzylic cation center.
用烷基胺辐照邻烯基
苯酚会产生马尔科夫尼科夫式胺化反应,从而得到邻(1-烷基
氨基烷基)
苯酚,产量相对较高。在
酚和胺之间形成的离子对的激发态中,质子从
铵离子转移到邻烯基
苯酚阴离子的烯基,从而引发了光胺化反应。由此产生的齐聚物离子允许胺在苄基阳离子中心进行亲核加成。