Halogenative Dearomatization Of Sulfonated Naphthols

Dearomatization,an efficient synthetic strategy which plays an important role in organic synthesis,could construct complicated molecular structures directly and economically.On the other hand,sulfonated structures are widely present in natural products and drug molecules which have biologically activties.Therefore,the development of synthetic methods based on dearomatization strategies for the synthesis of compounds containing sulfonyl-substituted structures has an important practical application value.On the basis of summarizing literatures,the halogenative dearomatization of 1-sulfonyl-2-naphthol compounds was systematically studied in this thesis.Firstly,a halogenative dearomatization of 1-sulfonyl-2-naphthol compounds based on an aqueous system under alkaline conditions was developed,and the corresponding products containing a double heteroatomic subsititued quaternary-carbon center were obtained with high yields(up to 99% yield)in a short reaction time.This reaction provided a green synthesis method for a class of sulfonated naphthone derivatives containing double heteroatomic subsititued quaternary-carbon center.Secondly,with the using of chiral tertiary amine-squaramide acid compounds,an asymmetric chlorinative dearomatization reactions of sulfonated naphthols compounds were developed in this thesis.A series of sulfonated naphthones with a chiral quaternary-carbon center substituted by a chlorine atom and sulfur atom were abtained with high-yield and enantioselective(up to 95% yield,up to 94% ee)All in all,the halogenative dearomatization of sulfonated naphthols was studied systematically in this thesis for the first time.The sulfonated naphthones containing quaternary carbon centers were obtained under environmentally friendly conditions;And the asymmetric catalytic chlorinative reaction of sulfonated naphthols was also realized using tertiary amine-squaramide organocatalyst.