Synthesis of Benzimidazoles and Benzoxazoles Using Palladium Bis(2,2,6,6-tetramethyl-3,5-heptanedionate) as a Novel Catalyst

Abstract

Structurally well-defined palladium bis(2,2,6,6-tetramethyl-3,5-heptanedionate) complex is reported to be an efficient catalyst for the synthesis of benzimidazole and benzoxazole derivatives in good yields. A novel approach for one-pot synthesis of benzimidazoles via direct reductive amination and N-arylation followed by hydrogenation–cyclization methodology is also described.

Keywords:

• Benzimidazoles
• DRA
• hydrogenation
• N-arylation
• Pd(TMHD)₂ complex

Notes

^a Reaction conditions as given in the Experimental section.

^b Isolated yield.

^a GC yield.

^a GC yield.