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Copper-Catalyzed Benign and Efficient Oxidation of Tetrahydroisoquinolines and Dihydroisoquinolines Using Air as a Clean Oxidant.

ABSTRACT: A green chemical method for mild oxidation of 1,2,3,4-tetrahydroisoquinolines (THIQs) and 3,4-dihydroisoquinolines (DHIQs) has been developed using air (O2) as a clean oxidant. DHIQs and THIQs could be efficiently oxidized to isoquinolines in dimethyl sulfoxide at 25 °C under an open air atmosphere with CuBr2 (20 mol %) as the catalyst; different bases [NaOEt and/or 1,8-diazabicyclo[5,4,0]undec-7-ene] were used for the reaction according to the patterns of substituents (R1, R2).

SUBMITTER: Zheng B

PROVIDER: S-EPMC6644811 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature

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Copper-Catalyzed Benign and Efficient Oxidation of Tetrahydroisoquinolines and Dihydroisoquinolines Using Air as a Clean Oxidant.

Zheng Bo B Trieu Tien Ha TH Li Feng-Lei FL Zhu Xing-Liang XL He Yun-Gang YG Fan Qi-Qi QQ Shi Xiao-Xin XX

ACS omega 20180724 7

A green chemical method for mild oxidation of 1,2,3,4-tetrahydroisoquinolines (THIQs) and 3,4-dihydroisoquinolines (DHIQs) has been developed using air (O<sub>2</sub>) as a clean oxidant. DHIQs and THIQs could be efficiently oxidized to isoquinolines in dimethyl sulfoxide at 25 °C under an open air atmosphere with CuBr<sub>2</sub> (20 mol %) as the catalyst; different bases [NaOEt and/or 1,8-diazabicyclo[5,4,0]undec-7-ene] were used for the reaction according to the patterns of substituents (R<s ...[more]

PMID: 31458961

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