Metal-free cycloaddition to synthesize naphtho[2,3-d][1,2,3]triazole-4,9-diones

Abstract

A metal-free domino [3 + 2] cycloaddition is reported to construct naphtho[2,3-d][1,2,3]triazole-4,9-dione derivatives and provide an alternative approach to the azide-alkyne cycloadditions. The key features are easily available starting materials, mild reaction conditions, a good atom economy, eco-friendly characteristics and a broad substrate scope with high yields.

Cerium(III) triflate–catalyzed cycloaddition reaction in aqueous conditions to substituted naphthotriazolediones

“…One of the proposed mechanisms for the cycloaddition of 1,4-naphthoquinone with azides under metal-free conditions has been reported by Wang's group. [9] Herein, a proposed reaction mechanism for the synthesis of naphthotriazolediones under catalyst-assisted conditions is illustrated in Scheme 3. [9,19] The reaction can be explained as being initiated by the Ce(OTf) 3 -catalyzed cycloaddition of 1,4-naphthoquinone 1 and azides 2.…”

“…[ 14 ] However, relatively few studies have investigated the applications and synthesis of substituted naphthotriazolediones. [ 9,15 ] Hence, the development of a general protocol that can be feasibly applied and is scalable for industrial applications is required.…”

Sequential, One‐Pot Access to Arylated Benzoquinones/Naphthoquinones from Phenols/Naphthols

“…The reaction between 1‐naphthol ( 1a ) and N , N ‐dimethylaniline ( 2a ) was chosen as the model for optimization studies (Table 1). Recently, our group were interested in developing sequential one‐pot reactions and we conceived that a similar strategy could be employed to construct arylated quinones 9a,9d–9f. Through reference to literature reports, the oxidation of 1‐naphthol ( 1a ) to naphthoquinone ( 1a′ ) was optimized by using meta ‐chloroperoxybenzoic acid ( m ‐CPBA; 2 equiv.)…”

Progress in the Synthesis of Fused 1,2,3‐Triazoles

“…Chen et al [114] . developed a metal‐free synthesis of naptho[2,3‐ d ][1,2,3]triazole‐4,9‐diones 359 .…”