Synthesis of Isoquinolinium-2-yl Amides via Silver(I)-Catalyzed Ring Closure of N′-(2-Alkynylbenzylidene)hydrazides

Abstract

An efficient one-pot protocol for the synthesis of isoquinolinium-2-yl amides starting from readily available hydrazides and 2-alkynylbenzaldehydes is described. The key step of the protocol is a silver(I)-catalyzed ring-closure of N′-(2-alkynylbenzylidene)hydrazides that are generated in situ. Isoquinolinium-2-yl amides derived from tert-butoxycarbonyl hydrazide could be further deprotected, delivering 2-aminoisoquinolinium trifluoroacetates.

alkynes - hydrazides - isoquinolines - annulation - ylides - silver catalysis

References

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10

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