title: Gold(I)-catalyzed 1,2-acyloxy migration/[3+2] cycloaddition of 1,6-diynes with an ynamide propargyl ester moiety: highly efficient synthesis of functionalized cyclopenta[b]indoles.
abstract: A gold-catalyzed cycloisomerization of 1,6-diynes containing an ynamide propargyl ester or carbonate moiety has been developed that provides an attractive route to a diverse-substituted 3-acyloxy-1,4-dihydrocyclopenta[b]indoles. Mechanistic studies indicate that the reaction likely proceeds through a competitive 1,2-OAc migration followed by [3+2] cycloaddition of the vinyl gold-carbenoid intermediate with the pendant triple bond. The synthetic utility of the obtained cyclopenta[b]indole products was demonstrated by their efficient transformations by deprotection or double-bond isomerization reactions.
authors.affiliation: State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032 (P. R. China).
authors.forename: Jun
authors.initials: J
authors.lastname: Liu
authors.forename: Ming
authors.initials: M
authors.lastname: Chen
authors.forename: Liangwei
authors.initials: L
authors.lastname: Zhang
authors.forename: Yuanhong
authors.initials: Y
authors.lastname: Liu
mesh_terms: D000577:Amides / Q000737:chemistry*; D002384:Catalysis; D056831:Coordination Complexes / Q000737:chemistry; D061565:Cycloaddition Reaction; D003517:Cyclopentanes / Q000737:chemistry; D053280:Diynes / Q000737:chemistry*; D004952:Esters; D006046:Gold / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D007536:Isomerism
chemical_list: D000577:Amides; D056831:Coordination Complexes; D003517:Cyclopentanes; D053280:Diynes; D004952:Esters; D007211:Indoles; D006046:Gold; C030374:indole
keywords: cycloaddition; gold; homogeneous catalysis; propargyl ester; ynamides