Alkoxide-catalyzed regioselective and reductive functionalization of N-heterocycles using organoboron reagents

Abstract

Synthesis of dearomative heterocycles has been experienced as an important building unit in synthetic and medicinal chemistry such as marketed drugs, intermediates for biorelevant compounds. In this context, a growing emphasis has been placed on the selective reduction and functionalization of N-heteroarenes, since they provide an efficient platform to access value-added compounds. This dissertation describes combination of alkoxide bases with electrophilic organoboranes could be an effective catalytic system for dearomative reduction of pyridines leading to N-boryl-dihydropyridines Also, we develop a highly efficient KOtBu-catalyzed C2-selective silaboration of N-heteroarenes including both pyridines and quinolines by means of the dearomatization strategy. These labile compounds could be isolated either as their N-acyl derivatives or as rearomatized 2-silyl-N-heteroarenes by the convenient one-pot procedures. Mechanistic studies combined with experiments and computations unveil the origin of regioselectivity by revising ion pair mechanism.