Silver promoted Nazarov reaction

The cascade sequences presented herein demonstrate unprecedented modes of reactivity in Nazarov chemistry that are initiated by the silver(I)-promoted ring opening of halocyclopropanes. The ease with which the gem-dichlorocyclopropanes can be prepared, the relatively mild reaction conditions, and the efficiency of these processes make these substrates attractive intermediates for an application in natural product synthesis. 

The synthesis of nitrogen heterocycles has been achieved through variations of intramolecular imino-Nazarov cycUzations (Schemes 3.26 and 3.27) [26], A silver-catalyzed version of the reaction generated indolines in moderate to good yields from a range of functionalized aldehydes and secondary amines, while a gadolinium-promoted reaction afforded fused tetrahydroquinoline derivatives in moderate yields. 

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