Highly selective C3-H iodination of pyrrolo[1,2-a]quinoxalines

Copper-promoted direct sulfenylation of C1-H bonds in 4-aryl pyrrolo[1,2-a]quinoxalines

Methods for direct functionalization of C(sp2)-H bonds in pyrrolo[1,2-a]quinoxalines have witnessed emerging development over the last decade. Herein we report a new tactic to afford a selective sulfenylation of 4-aryl pyrrolo[1,2-a]quinoxalines with diaryl disulfides. The reactions proceeded in the presence of a copper catalyst and potassium iodide promoter. Functionalities including nitro, ester, amide, methylthio, and halogen groups were all tolerated. Our method offers a convenient route to obtain highly substituted pyrrolo[1,2-a]quinoxalines-based thioethers in moderate to good yields.

Synthesis, Crystal Structure and Anti-Leukemic Activity of 1,3-Dihydro-1-{1-[4-(4-phenylpyrrolo[1,2-a]quinoxalin-3-yl)benzyl]piperidin-4-yl}-2H-benzimidazol-2-one

1,3-Dihydro-1-{1-[4-(4-phenylpyrrolo[1,2-a]quinoxalin-3-yl)benzyl]piperidin-4-yl}-2H-benzimidazol-2-one has been synthesized through a multi-step pathway starting from commercially available 2-nitroaniline. A structure characterization of this new substituted pyrrolo[1,2-a]quinoxaline compound was achieved by using FT-IR, 1H-NMR, 13C-NMR, X-Ray and HRMS spectral analysis. This new pyrroloquinoxaline derivative shows an interesting cytotoxic potential against several human leukemia cell lines (HL60, K562 and U937 cells).

Pd-Catalyzed direct C-H arylation of pyrrolo[1,2-a]quinoxalines

An efficient Pd-catalyzed direct C-H arylation of pyrrolo[1,2-a]quinoxalines with aryl iodides is described, providing a selective route toward a series of 1-arylated and 1,3-diarylated pyrrolo[1,2-a]quinoxalines in good yields. This method features a broad substrate scope, good functional group tolerance and gram-scale synthesis. Furthermore, the C3-thiocyanation of the arylated product is also achieved. We believe that these novel aryl-substituted pyrrolo [1,2-a]quinoxalines will have a variety of applications in organic synthesis and medicinal chemistry.

p-Toluenesulfonic acid-catalyzed regioselective C4–H iodination of isoquinolin-1(2H)-ones

An efficient procedure for p-toluenesulfonic acid-catalyzed iodination of isoquinolin-1(2H)-ones with N-iodosuccinimide under mild reaction conditions is reported. This methodology features scalable synthesis, wide substrate scope, and high functional-group tolerance.