Department of Chemistry, Faculty of Science, Masaryk University , Kotlářská 2, 611 37 Brno, Czech Republic.
Laboratory of Growth Regulators, Faculty of Science, Palacký University & Institute of Experimental Botany ASCR , Šlechtitelů 27, 783 71 Olomouc, Czech Republic.
J Org Chem. 2016 Dec 2;81(23):11841-11856. doi: 10.1021/acs.joc.6b02230. Epub 2016 Nov 10.
C-H activation of position 3 of a substituted pyrazole ring catalyzed by palladium(II) was straightforward and convenient for arylated or heteroarylated 5,5-dimethyl-5,6-dihydro-4H-pyrrolo[1,2-b]pyrazoles. Moreover, we introduced simple protection of the nitrogen in the pyridin-2-yl directing group, which otherwise does not allow a cross-coupling reaction, by transformation to the N-oxide. Selected final products were reasonably selective ALK5 kinase inhibitors.
钯（II）催化取代吡唑环 3 位的 C-H 活化对于芳基化或杂芳基化 5,5-二甲基-5,6-二氢-4H-吡咯并[1,2-b]吡唑来说是直接而方便的。此外，我们通过转化为 N-氧化物对吡啶-2-基导向基团中的氮进行了简单的保护，否则该导向基团将不允许进行交叉偶联反应。所选的最终产物是合理的选择性 ALK5 激酶抑制剂。
