Obulesu Owk, Murugesh V, Harish Battu, Suresh Surisetti
Organic and Biomolecular Chemistry Division , CSIR-Indian Institute of Chemical Technology (CSIR-IICT) , Hyderabad 500 007 , India.
Academy of Scientific and Innovative Research (AcSIR) , New Delhi 110 025 , India.
J Org Chem. 2018 Jun 15;83(12):6454-6465. doi: 10.1021/acs.joc.8b00746. Epub 2018 Jun 6.
A base-mediated tandem aza-Michael addition-vinylogous nitroaldol condensation has been described between 3,5-dialkyl 4-nitropyrazoles and alkynyl ketones/aldehydes. This transition metal-free atom economical transformation occurred via C-N and C═C bond formations in one step with the elimination of water. The construction of a variety of highly substituted N-fused 3-nitropyrazolopyridine derivatives has been demonstrated with good yields. Good to excellent regioselectivities have been achieved with unsymmetrically substituted 4-nitropyrazoles.
已报道了在3,5-二烷基-4-硝基吡唑与炔基酮/醛之间发生的碱介导的串联氮杂-Michael加成-乙烯型硝基羟醛缩合反应。这种无过渡金属的原子经济转化通过一步形成C-N键和C═C键并消除水来实现。已证明可以高收率构建各种高度取代的N-稠合3-硝基吡唑并吡啶衍生物。对于不对称取代的4-硝基吡唑，已实现了良好至优异的区域选择性。
