Combination of the Suzuki–Miyaura cross-coupling and nucleophilic aromatic substitution of hydrogen (image) reactions as a versatile route to pyrimidines bearing thiophene fragments

It has been shown that combination of the Suzuki–Miyaura cross-coupling and nucleophilic aromatic substitution of hydrogen is a versatile method for the synthesis of 4-(thiophen-2-yl)-, 5-(thiophen-2-yl)-, and 4,5-di(thiophen-2-yl) substituted pyrimidines from the commercially available 5-bromopyrimidine. The image (AE)- and image (AO)-reactions of 5-bromopyrimidine with thiophene and 2-bromothiophene have been studied by gas–liquid chromatography/mass-spectrometry. The structures of intermediate σH-adducts, as well as thiophene-(thiophenyl)pyrimidine and bithiophene-(thiophenyl)pyrimidine dyads have first been established by X-ray crystallography analysis.