Polymethoxy-substituted phenanthrene-9-carboxylic acids or their methylate are key intermediates for the synthesis of tylophora alkaloids and their analogs. An intramolecular oxidative coupling reaction of unfunctiona...Polymethoxy-substituted phenanthrene-9-carboxylic acids or their methylate are key intermediates for the synthesis of tylophora alkaloids and their analogs. An intramolecular oxidative coupling reaction of unfunctionalized 2,3-disubstituted phenyl acrylic acids and derivatives promoted by di-tert-butylper- oxide gave above intermediates in high yields. The mild reaction conditions and easy purification procedures of this method provide a new approach for the synthesis of phenanthrenes.展开更多
A mild synthetic method of a series of phenanthrenes with different substituents on the phenanthrene ring is described.The method involves intramolecular oxidative coupling with 2,3-dichloro-5,6-dicyanobenzoquinone （...A mild synthetic method of a series of phenanthrenes with different substituents on the phenanthrene ring is described.The method involves intramolecular oxidative coupling with 2,3-dichloro-5,6-dicyanobenzoquinone （DDQ）/trifluoroacetic acid（TFA） as oxidant to produce phenanthrenes in high yields and is fit for large-scale preparation.Furthermore,DDQ can be regenerated by a simple oxidation.The present approach solves a key step for the synthesis of polycyclic structures related to an alkaloid tylophorine.展开更多
Two new lignans with dibenzocycloheptadiene skelectons have been synthesized by intramolecular nonphenolic oxidative coupling and rearrangement. The structures of these products have been identified by MS, UV, IR and ...Two new lignans with dibenzocycloheptadiene skelectons have been synthesized by intramolecular nonphenolic oxidative coupling and rearrangement. The structures of these products have been identified by MS, UV, IR and NMR spectra.展开更多
基金Sichuan Provincial Education Department(No.12ZA141)Key Laboratory of Advanced Functional Materials of Sichuan Province Higher Education System (No.KFKT2013-01)Sichuan Normal University(No.XYZ201314-37)for financial support
文摘Polymethoxy-substituted phenanthrene-9-carboxylic acids or their methylate are key intermediates for the synthesis of tylophora alkaloids and their analogs. An intramolecular oxidative coupling reaction of unfunctionalized 2,3-disubstituted phenyl acrylic acids and derivatives promoted by di-tert-butylper- oxide gave above intermediates in high yields. The mild reaction conditions and easy purification procedures of this method provide a new approach for the synthesis of phenanthrenes.
基金Supported by the National Key Project for Basic Research of China（No.2010CB126100）, the National Natural Science Foundation of China（Nos.21132003, 21121002, 21372131） and the Specialized Research Fund for the Doctoral Program of Higher Education of China（No.20120031110010）.
文摘A mild synthetic method of a series of phenanthrenes with different substituents on the phenanthrene ring is described.The method involves intramolecular oxidative coupling with 2,3-dichloro-5,6-dicyanobenzoquinone （DDQ）/trifluoroacetic acid（TFA） as oxidant to produce phenanthrenes in high yields and is fit for large-scale preparation.Furthermore,DDQ can be regenerated by a simple oxidation.The present approach solves a key step for the synthesis of polycyclic structures related to an alkaloid tylophorine.
文摘Two new lignans with dibenzocycloheptadiene skelectons have been synthesized by intramolecular nonphenolic oxidative coupling and rearrangement. The structures of these products have been identified by MS, UV, IR and NMR spectra.
