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CuBr₂-Catalyzed Mild Oxidation of 3,4-Dihydro-?-Carbolines and Application in Total Synthesis of 6-Hydroxymetatacarboline D.

ABSTRACT: A green chemical method for the conversion of 3,4-dihydro-?-carbolines to ?-carbolines has been developed using air as the oxidant. With 15 mol % CuBr₂ as the catalyst, 3,4-dihydro-?-carbolines could be efficiently oxidized to ?-carbolines in dimethyl sulfoxide at room temperature in the presence of 1,8-diazabicyclo[5,4,0]undec-7-ene (or Et₃N). By applying this method, the first total synthesis of 6-hydroxymetatacarboline D was performed through 12 steps in 22% overall yield starting from l-5-hydroxy-tryptophan.

SUBMITTER: Meng TZ

PROVIDER: S-EPMC6641302 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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CuBr2-Catalyzed Mild Oxidation of 3,4-Dihydro-β-Carbolines and Application in Total Synthesis of 6-Hydroxymetatacarboline D.

Meng Tian-Zhuo TZ Zheng Jie J Trieu Tien Ha TH Zheng Bo B Wu Jia-Jia JJ Zhang Yi Y Shi Xiao-Xin XX

ACS omega 20180117 1

A green chemical method for the conversion of 3,4-dihydro-β-carbolines to β-carbolines has been developed using air as the oxidant. With 15 mol % CuBr2 as the catalyst, 3,4-dihydro-β-carbolines could be efficiently oxidized to β-carbolines in dimethyl sulfoxide at room temperature in the presence of 1,8-diazabicyclo[5,4,0]undec-7-ene (or Et3N). By applying this method, the first total synthesis of 6-hydroxymetatacarboline D was performed through 12 steps in 22% overall yiel ...[more]

PMID: 31457912

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