This review summarizes the synthesis and reactivity of N-aminopyridinium salts, discusses applications in organic synthesis, and highlights the potential for these reagents to enable novel synthetic disconnections and innovations.
A method for the construction of 2-fluoropyrazolo[1,5-a]pyridines through base-promoted [3+2] cycloaddition of N-aminopyridinium salts with gem-difluorostyrenes has been established.
A base-promoted [3+2] cycloaddition between N-aminoisoquinolinium/N-aminoquinolinium derivatives and cyclic iodonium ylides/2,2-difluorovinyl tosylate has been developed.
As a carbene precursor, diazo compounds incorporate in Rh-catalyzed synthesis of heterocycles, carbocycles and functionalized compounds. The reaction involves C–H activation, carbene insertion and an annulation/functionalization sequence.
This review article summarizes the synthesis of iodonium ylides and its potential applications in C–H funtionalizations/annulations, including nitrogen heterocycles, oxygen heterocyles, alkenylations, etc.