Regiodivergent C–H alkynylation of 2-arylthiazoles switched by RuII and PdII catalysis

Abstract

Two complementary regiodivergent C–H alkynylations of 2-arylthiazoles are reported. When Ru^II catalysis is employed, an aryl ortho-alkynylation process is favored. The alkynylated products are gained in good yields. With the use of Pd^II catalysis, a thiazole C5-alkynylation process is developed, allowing for the construction of C5-alkynylated products. This strategy not only expands the methods for the functionalization of 2-arylthiazoles, but also provides new opportunities for the rapid assembly of complex molecular structures, which may have great potential in organic synthesis, medicinal chemistry, and materials science.