A new and efficient procedure for the synthesis of hexahydropyrimidine-fused 1,4-naphthoquinones

2-Amino-1,4-naphthoquinone as a key precursor for naphthoquinone-fused N-heterocycles: synthetic approaches and mechanistic perspectives

2-Amino-1,4-naphthoquinone has gained significant attention as a key precursor for constructing naphthoquinone-fused N-heterocycles, a class of compounds with broad applications in medicinal chemistry, materials science, and organic synthesis. Its unique structure, characterized by a reactive C-3 position and an amino group, facilitates a wide range of reactions and synthetic strategies. This review provides a comprehensive overview of recent advancements (2012-2024) in utilizing 2-amino-1,4-naphthoquinone for the development of N-heterocyclic frameworks integrating synthetic approaches with mechanistic insights. It is organized based on the type of heterocyclic rings formed, leveraging the C,N-binucleophilic properties of 2-amino-1,4-naphthoquinone.

Additive-Free Construction of Tetrahydropyrimidine Skeleton by using 1,3,5-Triazinane as Four-Atom Synthon

Herein, an unprecedented [4 + 2] cycloaddition of enaminone with 1,3,5-triazinane has been developed. The representative semihydrogenated aromatic heterocycle 1,2,3,4-tetrahydropyrimidines have been synthesized with a broad substrate scope, demonstrating potential antitumor activity. This approach has been smoothly conducted under additive-free and environmentally friendly conditions that are compatible with various functional groups. Furthermore, the condition optimization process reveals that the tetrahydropyrimidine product is regulated via the reaction temperature.

Octahydropyrimido[4,5-g]quinazoline-5,10-diones: their multicomponent synthesis, self-assembly on graphite and electrochemistry

A green multicomponent synthesis of previously unreported octahydropyrimido[4,5-g]quinazoline-5,6-diones was developed from simple building blocks. These highly symmetrical compounds show strong propensity to self-assembled molecular network (SAMN) formation on highly oriented pyrolytic graphite. The SAMN type is easily tunable by changing molecular characteristics. The redox behavior was studied by cyclic voltammetery.

Synthesis of α-Amino Tertiary Alkylperoxides by Lewis Acid-Catalyzed Peroxidation of 1,3,5-Triazines

α-Substituted peroxides have been found in natural products and are widely used as anti-malarial agents. Zn(OTf)₂ -catalyzed peroxidation of 1,3,5-triazines has been developed, accessing diversely substituted α-amino tertiary alkylperoxides with high efficiency. Mechanistic investigations and useful synthetic application of the products have also been presented.

Recent Advances of 1,3,5-Triazinanes in Aminomethylation and Cycloaddition Reactions

1,3,5-Trisubstituted 1,3,5-triazinanes (hexahydro-1,3,5-triazines), as stable and readily available surrogates for formaldimines, have found extensive applications for the construction of various nitrogen-containing compounds. The formaldimines, formed in situ from this reagent class, can participate in various aminomethylation and cycloaddition­ reactions. This short review presents recent advances in this field with emphasis on the conceptual ideas behind the developed methodologies and the reaction mechanisms.

1 Introduction

2 Aminomethylations with 1,3,5-Triazinanes

3 Cycloadditions with 1,3,5-Triazinanes

3.1 Use of 1,3,5-Triazinanes as Two-Atom Synthons

3.2 Use of 1,3,5-Triazinanes as Three-Atom Synthons

3.3 Use of 1,3,5-Triazinanes as Four-Atom Synthons

3.4 Use of 1,3,5-Triazinanes as Six-Atom Synthons

4 Conclusions