Regiodivergent Hydration–Cyclization of Diynones under Gold Catalysis
作者:Marta Solas、Miguel A. Muñoz、Samuel Suárez-Pantiga、Roberto Sanz
DOI:10.1021/acs.orglett.0c02892
日期:2020.10.2
Skipped diynones, efficiently prepared from biomass-derived ethyl lactate, undergo a tandem hydration–oxacyclization reaction under gold(I) catalysis. Reaction conditions have been developed for a switchable process that allows selective access to 4-pyrones or 3(2H)-furanonesfrom the same starting diynones. Further application of this methodology in the total synthesis of polyporapyranone B was demonstrated
Atom-Economic Synthesis of 4-Pyrones from Diynones and Water
作者:Yan-Li Xu、Qing-Hu Teng、Wei Tong、Heng-Shan Wang、Ying-Ming Pan、Xian-Li Ma
DOI:10.3390/molecules22010109
日期:——
Transition-metal-free synthesis of 4-pyrones via TfOH-promoted nucleophilic addition/cyclization of diynones and water has been developed. This transformation is simple, atom economical and environmentally benign, providing rapid and efficient access to substituted 4-pyrones.
Synthesis of 4-Pyrones by Formal Hydration of 1,3-Diynones Promoted by 1,4-Addition of Piperidine
作者:Erandi Liyanage Perera、Daesung Lee
DOI:10.1021/acs.orglett.2c02914
日期:2022.9.30
A new approach for the synthesis of 4-pyrones with broader substrate scope and functional group tolerance is described. The reaction proceeds via an initial 1,4-addition by piperidine, followed by nitrogen-assisted 6-endo-dig cyclization and hydrolysis. 1,3-Diynones with nonenolizable electron-withdrawing ketones and nonpropargylic H provide relatively high yields. For substrates with particular R2
描述了一种合成具有更广泛底物范围和官能团耐受性的 4-吡喃酮的新方法。该反应通过哌啶的初始 1,4-加成,然后是氮辅助 6 -endo-dig环化和水解进行。具有非烯醇化吸电子酮和非炔丙基 H 的 1,3-二炔酮提供相对较高的产率。对于具有特定 R 2取代基的底物,分离出 1,4- 或 1,6-加合物,这表明 R 2取代基的空间和电子因素应该对 6 -endo-dig环化产生强烈影响。
Al-Jobour, Nazar H.; Shandala, Mowafaq Y., Journal of Heterocyclic Chemistry, 1980, vol. 17, p. 941 - 944
作者:Al-Jobour, Nazar H.、Shandala, Mowafaq Y.
DOI:——
日期:——
AL-JOBOUR N. H.; SHANDALA M. Y., J. HETEROCYCL. CHEM., 1980, 17, NO 5, 941-944