title: Catalyst-Dependent Stereodivergent and Regioselective Synthesis of Indole-Fused Heterocycles through Formal Cycloadditions of Indolyl-Allenes.
abstract: Stereo- and regioselective construction of poly-heterocycles, especially those with several contiguous stereocenters, is still a challenge. In this paper, catalyst-dependent stereodivergent and regioselective synthesis of indole-fused heterocycles through formal cycloadditions of indolyl-allenes has been developed. The reaction features total reversion of an all-carbon quaternary stereocenter when a gold or platinum complex was employed as the catalyst through [3 + 2] cycloaddition of allene with indole, affording different diazabenzo[a]cyclopenta[cd]azulenes as epimers, respectively. In addition, in the presence of IPrAuCl and AgNTf2, highly regioselective exo-type [2 + 2] cycloaddition was observed, in which allene served as a 2C synthon. This methodology provides a simple and straightforward approach for the construction of indole-fused tricyclic systems under mild conditions in an atom-economical way.
authors.affiliation: ‡Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, Meilong Road No. 130, Shanghai 200237, China.
authors.forename: Liang-Yong
authors.initials: LY
authors.lastname: Mei
authors.affiliation: †State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling-Ling Lu, Shanghai 200032, China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Wei
authors.affiliation: †State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling-Ling Lu, Shanghai 200032, China.
authors.forename: Xiang-Ying
authors.initials: XY
authors.lastname: Tang
authors.affiliation: †State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Ling-Ling Lu, Shanghai 200032, China.|‡Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science and Technology, Meilong Road No. 130, Shanghai 200237, China.
authors.forename: Min
authors.initials: M
authors.lastname: Shi
mesh_terms: D000466:Alkadienes / Q000138:chemical synthesis / Q000737:chemistry*; D002384:Catalysis; D061565:Cycloaddition Reaction; D006046:Gold / Q000737:chemistry; D006575:Heterocyclic Compounds, 3-Ring / Q000138:chemical synthesis* / Q000737:chemistry; D007211:Indoles / Q000138:chemical synthesis / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry; D013237:Stereoisomerism
chemical_list: D000466:Alkadienes; D006575:Heterocyclic Compounds, 3-Ring; D007211:Indoles; D010984:Platinum; C025947:propadiene; D006046:Gold; C030374:indole