当前位置: X-MOL 学术Green Chem. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Cycloamination strategies for renewable N-heterocycles
Green Chemistry ( IF 9.3 ) Pub Date : 2020/01/09 , DOI: 10.1039/c9gc03655e
Hu Li 1, 2, 3, 4, 5 , Haixin Guo 6, 7, 8, 9 , Zhen Fang 1, 2, 3, 4, 5 , Taku Michael Aida 9, 10, 11, 12, 13 , Richard Lee Smith 6, 7, 8, 9
Affiliation  

Biomass resources have infinite possibilities for introducing nitrogen, sulfur, or phosphorus heteroatoms into their structures by virtue of controllable carbon–heteroatom bond formation. In this review, cycloamination approaches for thermal (catalyst-free) and catalytic transformation of biomass feedstocks into N-heterocyclic molecules including mechanistic pathways are analyzed. Bottom-up (small molecule substrates) and top-down (large molecule substrates) are considered. Sustainable routes for synthesis of five-membered (pyrroles, pyrrolidones, pyrazoles, imidazoles), six-membered (pyridines, pyrazines), fused (indoles, benzimidazoles), and other relevant azaheterocycles are critically assessed. Production of biomass-derived six-, seven-, and eight-membered as well as fused N-heterocyclic compounds with present approaches have relatively low selectivities. Attention to methods for forming analogous sulfur or phosphorus heteroatom compounds from biomass resources using either bottom-up or top-down strategies appear to have been greatly overlooked. Synthetic auxiliaries (heating modes, nitrogen sources) that enhance reaction efficiency and tunability of N-heterocyclic ring size/type are considered and plausible reaction mechanisms for pivotal pathways are developed.

中文翻译:

可再生N-杂环的环化策略

由于可控的碳杂原子键形成,生物质资源具有将氮,硫或磷杂原子引入其结构的无限可能。在这篇综述中,分析了用于将生物质原料进行热(无催化剂)和催化转化为N-杂环分子(包括机理途径)的环胺化方法。考虑自下而上(小分子底物)和自上而下(大分子底物)。严格评估了五元(吡咯,吡咯烷酮,吡唑,咪唑),六元(吡啶,吡嗪),稠合(吲哚,苯并咪唑)和其他相关氮杂杂环的合成路线。生产源自生物质的六,七,使用本发明方法的八元以及稠合的N-杂环化合物具有较低的选择性。使用自下而上或自上而下的策略从生物质资源形成类似的硫或磷杂原子化合物的方法的注意似乎已被大大忽略。考虑了提高反应效率和N-杂环尺寸/类型的可调性的合成助剂(加热模式,氮源),并开发了可能的关键途径反应机理。
更新日期:2020-02-13
down
wechat
bug