US 10,894,771 B2Granted

Preparation method of N-substituted dibenzo[a,c]carbazole compound

AssigneeDalian University of Technology

InventorsSheng Zhang, Hengmin Ma, Tienan Jin, Ming Bao

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Abstract

Pharmaceutical and chemical intermediates and relevant chemicals, and relates to a novel preparation method of N-substituted dibenzo[a,c]carbazole compound. O-alkynylaniline and derivatives thereof as raw materials conduct a cascade cyclization reaction in an anhydrous organic solvent in the presence of catalysts, oxidants and additives, and are converted into the N-substituted dibenzo[a,c]carbazole compound. The preparation method of the N-substituted dibenzo[a,c]carbazole compound has fewer reaction steps, low cost of raw material, mild reaction conditions and convenient operation. Moreover, the obtained product has high yield and high purity, fully meets the quality requirements for drug intermediates, and provides favorable conditions for the industrial production.

Claims8

Dependent claims

A method for preparing N-substituted dibenzo[a,c]carbazole compound, the method comprising using o-alkynylaniline as a raw material, in an anhydrous organic solvent in the presence of catalyst, oxidant and additive, to obtain N-substituted dibenzo[a,c]carbazole compound, with a synthesis route as follows:

wherein R1 is selected from alkyl and Ph;
R2 is selected from alkyl and Ph;
R3 is selected from H, halides, alkyl and CF3;
R4 is selected from H, alkyl, halides, Ph, OMe and CO2Me;
a molar ratio of the o-alkynylaniline to the catalyst is 1:0.05 to I:0.2;
a molar ratio of the o-alkynylaniline to the oxidant is 1:1 to 1:10;
a molar ratio of the o-alkynylaniline to the additive is 1:0.1 to 1:5;
a molar concentration of the o-alkynylaniline is 0.01 mmol/mL to 2 mmol/mL;
the additive is one or a mixture of more than one of PivOH, HCOOH, CH3COOH, NaHCO3, NaHSO4, CH3COONa, K3PO4, AgSbF6 and AgBF4.

6 more elements

Dependencies are inferred from the claim text.