Anodic oxidation of 5-amino-1,4-naphthoquinone (ANQ) and synthesis of a conducting polymer (PANQ)

Rhodium-catalyzed C-H bond activation for the synthesis of quinonoid compounds: Significant Anti-Trypanosoma cruzi activities and electrochemical studies of functionalized quinones

Ruthenium(II)‐Catalyzed C–H Alkenylation of Quinones: Diversity‐Oriented Strategy for Trypanocidal Compounds

We report a new method for A-ring selenation of naphthoquinones and anthraquinones and discuss the relevant trypanocidal activity of the synthesized compounds. We have demonstrated three efficient strategies for the preparation of the target selenium derivatives, i.e. (a) copper(I) thiophene-2-carboxylate and in situ generated Santi's reagent were used to prepare selenium-substituted benzenoid quinones, (b) copper complexes and (c) carbon nanotube-supported copper ferrite as catalysts in the presence of AgSeR-salts were also used for the synthesis of selenium-containing quinoidal derivatives. These new methods provide efficient and practical strategies for the preparation of selenium-based quinones. In addition, we have discovered nine compounds with potent trypanocidal activity. The derivatives 2a–2e showed potent trypanocidal activity with IC50 values in the range of 13.3 to 37.0 μM.

Copper complexes and carbon nanotube–copper ferrite-catalyzed benzenoid A-ring selenation of quinones: an efficient method for the synthesis of trypanocidal agents

Quinone molecular films derived from aminoquinones

The syntheses of a series of 5-arylethynyl-1,4-naphthoquinones were carried out by the reaction of 5-iodonaphthoquinone with substituted cuprous acetylides.

5-arylethynyl-1,4-naphthoquinones

The bromine or iodine atom in the quinonoid ring devoid of +M substituent in the position neighboring to the halogen is replaced by acetylenic groups on treatment with CuI acetylides, prepared either beforehand or in situ, in a mixture of DMSO and CHCl3 in the presence of a Pd complex catalyst. A series of mono- and diacetylenic derivatives of 1,4-naphtho- and 1,4-benzoquinone were prepared.

Substitution of acetylenic groups for halogen in the quinonoid ring

1.

2-Phenylethynyl-1,4-naphthoquinone reacts with ammonia and primary and secondary amines to form oxidative amination products — 2-amino-3-phenylethynyl-1,4-naphthoquinones.




2.

The amino group in the quinoid ring of the α-naphthoquinone nucleus deactivates the triple bond of the neighboring acetylenic substituent with respect to nucleophiles. Groups with no + M effect do not cause such deactivation, and the corresponding acetylenylquinones add amines at the triple bond to form β-aminovinyl derivatives.

Reactions of 2-phenylethynyl-1,4-naphthoquinone and its derivatives with amines

5‐(arylethynyl)‐1,4‐naphthoquinones

1.

Condensation of 2-N,N-dialkylamino-3-bromo-1,4-naphthoquinones with terminal acetylenes under Pd-Cu catalytic conditions yields 2-N,N-dialkylamino-3-acetyleneyl-1,4-naphthoquinones.




2.

Acetylenic condensations were used for obtaining 2-alkoxy-3-acetylenyl-1,4-naphthoquinones from the corresponding 2-alkoxy-3-bromo derivatives.

V. S. Romanov

Papers

5-arylethynyl-1,4-naphthoquinones

Substitution of acetylenic groups for halogen in the quinonoid ring

Reactions of 2-phenylethynyl-1,4-naphthoquinone and its derivatives with amines

5‐(arylethynyl)‐1,4‐naphthoquinones

Acetylenic condensation of 2-N,N-dialkylamino- and 2-alkoxy-3-bromo-1,4-naphthoquinones