School of Chemistry, University of Hyderabad, Hyderabad 500046, India.
Org Biomol Chem. 2012 May 7;10(17):3538-55. doi: 10.1039/c2ob25165e. Epub 2012 Mar 23.
An efficient and direct approach to β-heteroarylated (C-N bond) ketones is demonstrated. Base promoted redox isomerization of propargyl alcohol to α,β-unsaturated ketone followed by conjugate addition to NH-heteroarenes affords a wide range of β-heteroarylated ketones in good to excellent yields. Aryl, heteroaryl, alkyl C(sp), and terminal alkynes containing unactivated propargyl alcohols effectively undergo redox-isomerization conjugate addition (RICA) with NH-heteroarenes. Reaction of 3-substituted pyrazoles or indazole with propargyl alcohols enables highly regioselective products. A diverse range of NH-bearing nucleophiles such as: pyrazoles, imidazole, triazoles, pyrrole, indoles and aniline participate in this reaction and deliver the corresponding β-heteroarylated ketones.
本文展示了一种高效、直接的方法来合成β-杂芳基(C-N 键)酮。炔丙醇在碱促进下发生氧化还原异构化生成α,β-不饱和酮,然后与 NH-杂芳烃进行共轭加成,得到了一系列广泛的β-杂芳基酮,产率良好至优秀。芳基、杂芳基、烷基 C(sp)和末端炔烃中含有未活化的炔丙醇,能有效地与 NH-杂芳烃发生氧化还原异构化共轭加成(RICA)反应。3-取代的吡唑或吲唑与炔丙醇反应能得到高区域选择性的产物。多种含 NH 的亲核试剂,如吡唑、咪唑、三唑、吡咯、吲哚和苯胺,都能参与此反应,并得到相应的β-杂芳基酮。