Cationic cyclizations and rearrangements promoted by a heterogeneous gold catalyst.
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ABSTRACT:
SUBMITTER: Vaidya T
PROVIDER: S-EPMC3969096 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:Homogeneous 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 C-C or C-heteroatom 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 gold-catalyzed novel intramolecular cycloisomerizations of nitrogen or oxygen-tethered cyclopropenes with propargylic esters. The reaction proceeded through different pathways according to different substituent styles, affording 5-azaspiro[2.5]oct-7-enes and bicyclo[4.1.0]heptanes.
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