A kind of preparation method of amido alkyl naphthol

Abstract

The invention relates to a preparation method of acylamino alkyl naphthol.The method includes the steps of sequentially adding beta-naphthol, an aldehyde compound, amide and catalyst salicylic acid in a reactor to react under the water bath heating condition at a temperature of 50 DEG C to 95 DEG C so as to obtain a reaction mixture after reaction ends, obtaining a rough product after washing the reaction mixture, and obtaining the pure product acylamino alkyl naphthol after the rough product is recrystallized and separated through absolute ethyl alcohol.The method is simple, low in production cost and high in efficiency and has product yield up to 92.8% and good industrial application prospects.

Description

technical field [0001] The invention relates to the field of organic synthesis chemistry, in particular to a preparation method of amido alkyl naphthol. Background technique [0002] Amino alkyl naphthols, as an important class of organic synthesis intermediates, have important uses in the synthesis of medicine, pesticides, asymmetric synthesis and natural products due to their special biological activity and pharmacological properties. In particular, derivatives of amidoalkylnaphthols transformed from amidoalkylnaphthols have remarkable effects in treating hypertension and cardiovascular diseases. Moreover, the ligands formed by its derivatives are also widely used as catalysts. [0003] In 2007, Patil etc. reported that under the assistance of ultrasound, using sulfamic acid as a catalyst, β-naphthol, aldehyde and amide reacted in dichloromethane or solvent-free medium to obtain the corresponding amido alkylnaphthol, although this method produces The reaction rate is hig...

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Problems solved by technology

[0003] In 2007, Patil etc. reported that under the assistance of ultrasound, using sulfamic acid as a catalyst, β-naphthol, aldehyde and amide reacted in dichloromethane or solvent-free medium to obtain the corresponding amido alkylnaphthol, although this method produces High efficiency and mild conditions, but the reaction time is long, up to 120min, and some reaction substrates need to be added with solvents (Ultrasonics Sonochemistry, 2007, 14, 515–518)

However, tetraethylammonium chloride needs to be added as a cocatalyst in this reaction, and the reaction temperature is high (100°C) and the reaction time is long (80min) (Archive for Organic Chemistry 2009, vii, 303-310) , 303-310)

In 2015, Barani et al. reported that lactic acid catalyzed the one-pot three-component reaction of β-naphthol, aldehyde and amide under solvent-free conditions, and obtained the corresponding products in high yields, but the reaction temperature was as high as 115°C and the reaction time was longer, up to 45 minutes (Iranian Journal of Catalysis, 2015, 5, 339-343)

In 2006, Khodaei et al. reported that p-toluenesulfonic acid catalyzed the three-component reaction of β-naphthol, aldehyde and amide in dichloromethane medium or solvent-free medium, and high yield obtained corresponding product amido alkylnaphthol, but this Whether the reaction is a solvent-free high temperature (120°C) reaction or a reaction in methylene chloride at room temperature, the time is too long (30~3h) (Synlett, 2006, 6,0916-0920 )

However, the reaction of salicylic acid substances for the preparation of amidoalkylnaphthols in a three-component one-pot method has not been reported in the literature at present.

[0005] As can be seen from the literature records, although the above method has mild reaction conditions and high yield, there are still many problems: (1) need to add co-catalyst; (2) long reaction time; (3) high reaction temperature; (4) need reaction solvent, high reaction cost