申请人:HOECHST CELANESE CORPORATION
公开号:EP0271307A2
公开(公告)日:1988-06-15
A method is provided for preparing alkenylthiophenols, e.g. para-vinylthiophenol, or their esters, e.g., para-vinylthiophenol acetate by reacting a hydroxy aromatic ketone, e.g., 4-hydroxyacetophenone (4-HAP) with an N,N-di(organo)thiocarbamoyl halide, e.g., N,N-dimethylthiocarbamoyl chloride (DMTC) to form an O-(acylaryl) N,N-di(organo)thiocarbamate, e.g., O-(4ʹ-acetophenyl) N,N-dimethylthiocarbamate, and pyrolytically rearranging the latter compound to form an S-(acylaryl) N,N-di(organo)thiocarbamate, e.g., S-(4ʹ-acetophenyl) N,N-dimethylthiocarbamate. In one procedure, the latter compound is directly reduced to form an S-(1-hydroxyalkylaryl) N,N-di(organo) thiocarbamate, e.g., S-[4ʹ-(1-hydroxyethyl)phenyl] N,N-dimethylthiocarbamate, which is either hydrolyzed to form a (1-hydroxyalkyl) thiophenol, e.g., 4ʹ-(1-hydroxyethyl) thiophenol, which, optionally after acylation of its thiol group, is dehydrated to form the alkenylthiophenol wherein the double bond is at the ring-bonded carbon atom, e.g., para-vinylthiophenol, or the S-(1-hydroxyalkylaryl) N,N-di(organo) thiocarbamate is dehydrated to form an S-(alkenylaryl) N,N-di(organo) thiocarbamate, e.g., S-(4-vinylphenyl) N,N-dimethylthiocarbamate which is hydrolyzed to form the alkenylthiophenol. In an alternative procedure, the S-(acylaryl) N,N-di(organo)thiocarbamate is hydrolyzed and the resulting thiol acylated with an acylating agent, e.g., acetyl chloride, to produce an acylthiophenol ester, e.g., 4-acetothiophenol acetate, which is then reduced and hydrolyzed to produce the (1-hydroxyalkyl) thiophenol. The latter compound is then dehydrated to produce the alkenylthiophenol, or acylated and dehydrated to produce the alkenylthiophenol thioester, as described in the first procedure.
本发明提供了一种制备烯基
苯硫酚(如对
乙烯基苯硫酚)或其
酯类(如对
乙烯基苯硫酚乙酸酯)的方法,该方法通过使羟基
芳香酮(如
4-羟基
苯乙酮(4-HAP))与 N,N-二(有机)
硫代
氨基甲
酰卤(如 N,N-二甲基
硫代氨基甲酰氯(
DMTC))反应,生成 O-(酰基)N,N-二(有机)
硫代
氨基甲酸酯(如 N,N-二甲基
硫代氨基甲酰氯(
DMTC))、N,N-二甲基
硫代氨基甲酰氯(
DMTC)形成 O-(酰基)N,N-二(有机)
硫代
氨基甲酸酯,如O-(4ʹ-
乙酰苯基) N,N-
二甲基硫代
氨基甲酸酯,并对后一种化合物进行热解重排,形成 S-(酰基) N,N-二(有机)
硫代
氨基甲酸酯,例如 S-(4ʹ-
乙酰苯基) N,N-
二甲基硫代
氨基甲酸酯。在一种工艺中,后一种化合物被直接还原形成 S-(1-羟基烷基芳基) N,N-二(有机)
硫代
氨基甲酸酯,例如 S-[4ʹ-(1-羟乙基)苯基] N,N-
二甲基硫代
氨基甲酸酯,后者被
水解形成(1-羟基烷基)
噻吩酚,例如4ʹ-(1-羟乙基)
噻吩酚,该
噻吩酚可选择在其
硫醇基酰化后脱
水形成烯基
噻吩酚,其中双键位于环键碳原子上,例如S-(1-羟基烷基芳基) N,N-二(有机)
硫代
氨基甲酸酯脱
水形成 S-(烯基芳基) N,N-二(有机)
硫代
氨基甲酸酯,例如 S-(4-
乙烯基苯基) N,N-
二甲基硫代
氨基甲酸酯,
水解形成烯基
苯硫酚。另一种方法是将 S-(酰基)N,N-二(有机)
硫代
氨基甲酸酯
水解,所得
硫醇与酰化剂(如
乙酰氯)酰化,生成酰基
苯硫酚酯(如 4-
乙酰苯硫酚乙酸酯),然后将其还原和
水解,生成(1-羟基烷基)
苯硫酚。然后将后一种化合物脱
水生成烯基
苯硫酚,或者如第一种方法所述,将其酰化并脱
水生成烯基
苯硫酚硫酯。