ABSTRACT An operationally straightforward method for the preparation of the new dibenzoxepino[4,5-d)pyrazoles is reported. Such protocol is amenable to construct multisubstituted electron-rich, -neutral and -poor dibenzoxepinopyrazoles which would not be easily obtained by other methods. The key step, the assemblage of o,o’-halohydroxy-4-5-diarylpyrazoles is conducted alternatively either by an biaryl-ether Ullmann reaction promoted by CuBr·SMe2 complex or by an Pd-catalyzed C-O bond formation using a bidentate ligand such as BINAP or DPPF).
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