Sikdar Papiya, Choudhuri Tathagata, Paul Suvam, Das Sourav, Bagdi Avik Kumar
Department of Chemistry, University of Kalyani, Kalyani, WB 741235, India.
ACS Omega. 2023 Jun 22;8(26):23851-23859. doi: 10.1021/acsomega.3c02270. eCollection 2023 Jul 4.
A one-pot methodology has been developed to synthesize 3-halo-pyrazolo[1,5-]pyrimidine derivatives through the three-component reaction of amino pyrazoles, enaminones (or chalcone), and sodium halides. The use of easily accessible 1,3-biselectrophilic reagents like enaminones and chalcone offers a straightforward approach for the synthesis of 3-halo-pyrazolo[1,5-]pyrimidines. The reaction proceeded through a cyclocondensation reaction between amino pyrazoles with enaminones/chalcone in the presence of KSO followed by oxidative halogenations by NaX-KSO. Mild and environmentally benign reaction conditions, wide functional group tolerance, and scalability of the reaction are the attractive facet of this protocol. The combination of NaX-KSO is also beneficial for the direct oxidative halogenations of pyrazolo[1,5-]pyrimidines in water.
已经开发出一种一锅法，通过氨基吡唑、烯胺酮（或查尔酮）和卤化钠的三组分反应来合成3-卤代吡唑并[1,5 -]嘧啶衍生物。使用烯胺酮和查尔酮等易于获得的1,3-双亲电试剂为合成3-卤代吡唑并[1,5 -]嘧啶提供了一种直接的方法。该反应通过氨基吡唑与烯胺酮/查尔酮在KSO存在下的环缩合反应进行，随后通过NaX-KSO进行氧化卤化。温和且环境友好的反应条件、广泛的官能团耐受性以及反应的可扩展性是该方法吸引人的方面。NaX-KSO的组合对于吡唑并[1,5 -]嘧啶在水中的直接氧化卤化也很有益。
