Three different reaction steps were combined to provide methods for preparing p-hydroxystyrene and p-hydroxycinnamic acid monomers from tyrosine. The three steps include reductive alkylation of tyrosine, followed by oxidation to the N-oxide, and thermal Cope elimination. During Cope elimination, either p-hydroxycinnamic acid or p-hydroxystyrene was produced depending on the absence or presence of base, respectively. Additionally, p-acetoxystyrene may be prepared by reacting the prepared p-hydroxystyrene either directly or after isolation with an acetylating agent.
将
酪氨酸转化为对羟基
苯乙烯和
对羟基肉桂酸单体的方法结合了三个不同的反应步骤。这三个步骤包括
酪氨酸的还原烷基化,随后氧化为N-氧化物,以及热库普消除。在库普消除过程中,根据是否存在碱,分别产生
对羟基肉桂酸或对羟基
苯乙烯。此外,通过将制备的对羟基
苯乙烯直接或在隔离后与乙酰化剂反应,可以制备对乙酰氧基
苯乙烯。