Highly Efficient and Versatile Pd-Catalyzed Direct Alkynylation of Both Azoles and Azolines
作者:Seok Hwan Kim、Sukbok Chang
DOI:10.1021/ol100488v
日期:2010.4.16
A highly efficient and versatile Pd-catalyzed directalkynylation reaction of heterocycles with 1-bromoalkynes was developed. The substrate scope of the reaction was very broad to include not only azoles but also azolines for the first time, thus offering an important advance in the direct functionalization of heterocycles.
The direct C−H alkynylation of azoles with alkynyl bromides proceeds efficiently in the presence of a nickel-based catalyst system. The reaction enables the introduction of various alkynyl groups bearing aryl, alkenyl, alkyl, and silyl substituents to the azole cores. In some cases, addition of a catalytic amount of CuI is observed to accelerate the direct coupling dramatically.
The copper-catalyzed directalkynylation of azoles with 1,1-dibromo-1-alkenes as electrophiles is described. These easily accessible substrates are a useful addition to the field of directalkynylations in an efficient and functional group tolerant reaction to provide a straightforward entry to diverse alkynyl heterocycles.
The present invention is concerned with substituted azole derivatives that selectively modulate, regulate, and/or inhibit signal transduction mediated by certain native and/or mutant proteine kinases implicated in a variety of human and animal diseases such as cell proliferative, metabolic, allergic, and degenerative disorders. In particular, several of these compounds are potent and selective Flt-3 inhibitors or/and syk inhibitors.