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abstracthomogeneous gold catalysts are interesting as they can act as potent carbophilic lewis acids to activate the  bonds of alkynes , allenes , and alkenes . 
 many impressive applications for the formation of cc or cheteroatom bonds have been found due to the excellent functional group compatibility of these catalysts and the air and moisture tolerance of their reactions . here 
 , we have developed goldcatalyzed novel intramolecular cycloisomerizations of nitrogen or oxygentethered cyclopropenes with propargylic esters . 
 the reaction proceeded through different pathways according to different substituent styles , affording 5azaspiro[2.5]oct7enes and bicyclo[4.1.0]heptanes .