849799-68-4Relevant academic research and scientific papers
Dual Gold-Catalyzed Three-Component Reaction: Efficient Synthesis of Indene-Fused Esters, Acids, and Lactones through Gold Vinylidene Intermediates
Yu, Congjun,Ma, Xiaodong,Chen, Bin,Tang, Bencan,Paton, Robert S.,Zhang, Guozhu
, p. 1561 - 1565 (2017/04/01)
A dual gold(I)-catalyzed three-component reaction was developed to prepare indene-fused carboxylic acid derivatives from diynes, alcohols, and pyridine N-oxides in both inter- and intramolecular fashions. The pyridine N-oxides were found to exhibit distinct selectivity unlike the α-oxo gold carbene intermediates in the well-developed gold-catalyzed oxidative functionalization of alkynes. Experimental studies and DFT calculations support double nucleophilic substitution of a gold vinylidene intermediate.
CO extrusion in homogeneous gold catalysis: Reactivity of gold acyl species generated through water addition to gold vinylidenes
Bucher, Janina,St?sser, Tim,Rudolph, Matthias,Rominger, Frank,Hashmi, A. Stephen K.
, p. 1666 - 1670 (2015/01/30)
Herein, we describe a new gold-catalyzed decarbonylative indene synthesis. Synergistic σ,π-activation of diyne substrates leads to gold vinylidene intermediates, which upon addition of water are transformed into gold acyl species, a type of organogold compound hitherto only scarcely reported. The latter are shown to undergo extrusion of CO, an elementary step completely unknown for homogeneous gold catalysis. By tuning the electronic and steric properties of the starting diyne systems, this new reactivity could be exploited for the synthesis of indene derivatives in high yields.
Grignard reagent/CuI/LiCl-mediated stereoselective cascade addition/cyclization of diynes: A novel pathway for the construction of 1-methyleneindene derivatives
Li, De-Yao,Wei, Yin,Shi, Min
supporting information, p. 15682 - 15688 (2013/11/19)
Diynes containing a cyclopropane group smoothly undergo a novel intramolecular and stereoselective cascade addition/cyclization reaction to produce the corresponding 1-methyleneindene derivatives in moderate to good yields. This interesting transformation is mediated by Grignard reagent/CuI with LiCl as an additive under mild conditions. The obtained product can easily be further functionalized through cyclopropyl ring opening. A plausible reaction mechanism has also been presented on the basis of deuterium labeling and control experiments. Diyne cyclization: Diynes containing a cyclopropane group undergo a novel intramolecular and stereoselective cascade addition/cyclization reaction to produce the corresponding 1-methyleneindene derivatives (see scheme). The transformation proceeds under mild conditions and is promoted by a combination of Grignard reagent Copyright
Platinum- and gold-catalyzed hydrative carbocyclization of oxo diynes for one-pot synthesis of benzopyrones and bicyclic spiro ketones
Das, Arindam,Chang, Hsu-Kai,Yang, Cheng-Hua,Liu, Rai-Shung
supporting information; experimental part, p. 4061 - 4064 (2009/05/27)
(Chemical Equation Presented) We report a one-pot synthesis of benzopyrones and tricyclic spiroketones from hydrative carbocyclization of oxodiyne substrates catalyzed by PtCl2 and PPh3AuCl/AgOTf, respectively. The distinct carbocyclizations with R and Au catalysts stem from their altered regioselectivity in the oxo-assisted hydration of the neighboring alkyne carbons.
Ruthenium-catalyzed aromatization of enediynes via highly regioselective nucleophilic additions on a π-alkyne functionality. A useful method for the synthesis of functionalized benzene derivatives
Odedra, Arjan,Wu, Chang-Jung,Pratap, Taduri Bhanu,Huang, Chun-Wei,Ran, Ying-Fen,Liu, Rai-Shung
, p. 3406 - 3412 (2007/10/03)
TpRu(PPh3)(CH3CN)2PF6 (10 mol %) catalyst effected the nucleophilic addition of water, alcohols, aniline, acetylacetone, pyrroles, and dimethyl malonate to unfunctionalized enediynes under suitable conditions (100 °C, 12-24 h) and gave functionalized benzene products in good yields. In this novel cyclization, nucleophiles very regioselectively attack the internal C1′ alkyne carbon of enediynes to give benzene derivatives as a single regioisomer. Experiments with methoxy substituents exclude the possible involvement of naphthyl cations as reaction intermediates in the cyclization of (o-ethynylphenyl) alkynes. Deuterium-labeling experiments indicate that the catalytically active species is ruthenium-π-alkyne rather than ruthenium-vinylidene species. This hypothesis is further confirmed by the aromatization of o-(2′-iodoethynyl)phenyl alkynes with alcohols. We propose a nucleophilic addition/insertion mechanism for this nucleophilic aromatization on the basis of a series of experiments.
