[5+2] Cyclization of N,N′‐Cyclic Azomethine Imines with 1,3,5‐Triazines: An Efficient Protocol for the Synthesis of Tetrazepine Derivatives

Abstract

An unprecedented formal [5+2] cyclization of N,N′‐cyclic azomethine imines with triazines has been realized, which provides a facile access to biologically important 1,2,4,6‐tetrazepine frameworks with overall high yields (up to 98% yield). This methodology is distinguished by not involving a metal catalyst, readily available starting materials, and operational simplicity, which involves the reassembly of two C−N bonds.

A Three‐Component Reaction to Construct β‐Aminonitroso‐α‐Diazocarbonyl Compounds under Metal‐Free Conditions

“…However, the diazo group is lost in the above excellent examples. In pursuit of our interest in the reactions of 1,3,5‐triazines [16] . Herein, we described a novel three‐component reaction of 1,3,5‐triazines, diazo reagents with tert ‐butyl nitrite for the synthesis of β‐aminonitroso‐α‐diazocarbonyl compounds under metal‐free conditions (Scheme 1e).…”

Research Progress of 1,3,5-Triazinanes in the Synthesis of Nitrogen-Containing Heterocycles

“…四氮杂环骨架代表了重要的且有吸引力的一类七 元氮杂环骨架, 它们在药物和农药化学中具有重要的生 物学特性 [62,63] . 2021 年, 王凯凯等 [64] 报道了无金属催化 合成四氮杂䓬103 的反应(Scheme 32). 亚胺叶立德 99 和 1,3,5-三嗪烷分别作为双原子和五原子合成子, 参与 N-磺酰基-1,2,3-三氮唑可通过铜催化炔-叠氮化物 的环加成反应顺利制得, 在适当的过渡金属催化剂作用 下, 可转化为 α-亚氨基金属卡宾, 因此引起了有机化学 工作者极大的研究兴趣 [65][66][67][68][69][70][71] .…”

Synthesis of Chromeno[2,3-d]pyrimidin-5-one Derivatives from 1,3,5-Triazinanes via Two Different Reaction Pathways

“…Among them, the application of 1,3,5-triazinane has been developed as a hot issue recently, − which is attributed to the versatile reaction modes of 1,3,5-triazinane (Scheme ). − 1,3,5-Triazinane could participate not only in aminomethylation − but also in various annulation reactions, where either two atoms (i.e., C–N) − or other desired segments containing multiple atoms could be introduced to the target products. For example, two units of C–N could be incorporated into the products once or via sequential reactions. − As for more atoms, the synthesis of pyrazolotetrazepin-7-ones from 1,3,5-triazinanes with N , N′ -cyclic azomethine imines via a formal (5 + 2) pathway was developed by Liu’s and our group, , respectively, where the products contain five atoms fragmented from the 1,3,5-triazinane.…”

“… − 1,3,5-Triazinane could participate not only in aminomethylation − but also in various annulation reactions, where either two atoms (i.e., C–N) − or other desired segments containing multiple atoms could be introduced to the target products. For example, two units of C–N could be incorporated into the products once or via sequential reactions. − As for more atoms, the synthesis of pyrazolotetrazepin-7-ones from 1,3,5-triazinanes with N , N′ -cyclic azomethine imines via a formal (5 + 2) pathway was developed by Liu’s and our group, , respectively, where the products contain five atoms fragmented from the 1,3,5-triazinane. A rhodium­(II)-catalyzed annulation reaction of N -sulfonyl-1,2,3-triazoles with 1,3,5-triazinanes to produce octahydro-1 H -purine derivatives was recently reported by Bao and co-workers using six atoms of 1,3,5-triazinane .…”