title: Synthesis of 2-spiropseudoindoxyls via an intramolecular nitroalkyne redox-dipolar cycloaddition cascade.
abstract: Novel spiropseudoindoxyls were synthesized in high yields via a fully regioselective Au(III)-catalyzed cycloisomerization of easily obtainable o-nitrophenylpropiolamides, followed by an intramolecular dipolar cycloaddition as key steps. This one-pot cascade reaction resulted in new tetracyclic pseudoindoxyls, which were hydrogenated toward the title compounds as single diastereomers via N-O cleavage. The mechanism of the gold catalyzed cycloisomerization was studied by DFT and suggests a reaction path without the intermediacy of gold carbenoid species in these cases.
authors.affiliation: Research Group of Organic Chemistry, Department of Chemistry and Department of Bio-Engineering Sciences, Faculty of Science and Bio-Engineering Sciences, and ‡Research Group of General Chemistry, Vrije Universiteit Brussel (VUB) , Pleinlaan 2, B-1050 Brussels, Belgium.
authors.forename: Niels
authors.initials: N
authors.lastname: Marien
authors.forename: Ben
authors.initials: B
authors.lastname: Brigou
authors.forename: Balazs
authors.initials: B
authors.lastname: Pinter
authors.forename: Frank
authors.initials: F
authors.lastname: De Proft
authors.forename: Guido
authors.initials: G
authors.lastname: Verniest
mesh_terms: D000480:Alkynes / Q000737:chemistry*; D002384:Catalysis; D061565:Cycloaddition Reaction; D006046:Gold / Q000737:chemistry; D007211:Indoles / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D009574:Nitro Compounds / Q000737:chemistry*; D010084:Oxidation-Reduction; D013141:Spiro Compounds / Q000138:chemical synthesis* / Q000737:chemistry
chemical_list: D000480:Alkynes; D007211:Indoles; D009574:Nitro Compounds; D013141:Spiro Compounds; D006046:Gold