Visible-Light-Induced C (sp3)–H Functionalization of Tosylhydrazones: Synthesis of Polysubstituted Pyrroles under Metal-Free Conditions
摘要:
Iodine catalyzed C (sp(3))-H functionalization of tosylhydrazones with beta-enamino esters under visible light irradiation for the synthesis of trisubstituted pyrroles has been described. The present method is also applicable to a alpha-substituted tosylhydrazones to yield the tetra-substituted pyrroles.
I2–TBHP-Catalyzed Oxidative Cross-Coupling of N-Sulfonyl Hydrazones and Isocyanides to 5-Aminopyrazoles
摘要:
I-2-TBHP-catalyzed oxidative cross coupling of N-sulfonyl hydrazones with isocyanides has been realized for the synthesis of 5-aminopyrazoles through formal [4 + 1] annulation via in situ azoalkene formation. Notable features are the metal/alkyne-free strategy, C-C and C-N bond formation, atom economy, catalytic I-2, broad functional group tolerance, good reaction yields, shorter time, and also applicability to one-pot methodology.