176910-65-9Relevant academic research and scientific papers
Modular synthesis of 3-substituted isocoumarinsviasilver-catalyzed aerobic oxidation/6-endoheterocyclization ofortho-alkynylbenzaldehydes
Wu, Hao,Wang, Yi-Chun,Shatskiy, Andrey,Li, Qiu-Yan,Liu, Jian-Quan,K?rk?s, Markus D.,Wang, Xiang-Shan
, p. 6657 - 6664 (2021/08/16)
A method involving silver-catalyzed aerobic oxidation/6-endoheterocyclization ofortho-alkynylbenzaldehydes to yield 3-substituted isocoumarins is described. The developed protocol allows convenient access to a range of synthetically useful 3-substituted isocoumarins and related fused heterocyclolactones in good to high yields, using silver tetrafluoroborate as the catalyst, and atmospheric oxygen as the terminal oxidant and the source of endocyclic oxygen. Mechanistic studies suggest the involvement of a free-radical pathway.
Catalytic asymmetric three-component reaction of 2-alkynylbenzaldehydes, amines, and dimethylphosphonate
Zou, Liangliang,Huang, Jiaying,Liao, Na,Liu, Yan,Guo, Qixiang,Peng, Yungui
supporting information, p. 6932 - 6937 (2020/09/15)
An efficient enantioselective synthesis of cyclic α-aminophosphonates via multicomponent reactions of 2-alkynylbenzaldehydes, amines, and dimethylphosphonate has been developed with the use of a chiral silver spirocyclic phosphate as the catalyst. This protocol provides straightforward access to a series of chiral C1-phosphonylated 1,2-dihydroisoquinoline derivatives with high yields (up to 99%) and high enantioselectivities (up to 94% ee) for a broad substrate scope. The products could be further transformed into densely functionalized compounds and corresponding α-aminophosphonic acids.
Regiospecific palladium-catalyzed cross-coupling reactions using the operational equivalent of 1,3-dilithiopropyne
Cabezas, Jorge A.,Ferllini, Natasha
, p. 2387 - 2394 (2020/09/09)
A regiospecific palladium-catalyzed cross-coupling reaction using the operational equivalent of the dianion 1,3-dilithiopropyne, with aromatic iodides is reported. This reaction gives high yields of 1-propyn-1-yl-benzenes and 2-(propyn-1-yl)thiophenes in
A Transient-Directing-Group Strategy Enables Enantioselective Reductive Heck Hydroarylation of Alkenes
Deng, Ruohan,Engle, Keary M.,Erbay, Tu??e G.,Li, Zi-Qi,Liu, Peng,Oxtoby, Lucas J.,Tran, Van T.
supporting information, p. 8885 - 8890 (2020/04/15)
Metal-coordinating directing groups have seen extensive use in the field of transition-metal-catalyzed alkene functionalization; however, their waste-generating installation and removal steps limit the efficiency and practicality of reactions that rely on their use. Inspired by developments in asymmetric organocatalysis, where reactions rely on reversible covalent interactions between an organic substrate and a chiral mediator, we have developed a transient-directing-group approach to reductive Heck hydroarylation of alkenyl benzaldehyde substrates that proceeds under mild conditions. Highly stereoselective migratory insertion is facilitated by in situ formation of an imine from catalytic amounts of a commercially available amino acid additive. Computational studies reveal an unusual mode of enantioinduction by the remote chiral center in the transient directing group.
Bioinspired Total Synthesis of (±)-Chaetophenol C Enabled by a Pd-Catalyzed Cascade Cyclization
Li, Yun,Zhang, Qingyu,Wang, Hongyu,Cheng, Bin,Zhai, Hongbin
supporting information, p. 4387 - 4390 (2017/08/23)
A novel Pd(II)-catalyzed cascade reaction has been developed that consists of a highly regio- and stereoselective oxa [4 + 2] cycloaddition reaction of o-alkynylbenzaldehydes and an intramolecular carboxylic group quenching of the in situ generated oxonium ion. This new reaction provides a one-step construction of the tetracyclic core structure of chaetophenol C from two simple starting materials. The developed chemistry was successfully applied to the first total synthesis of chaetophenol C and dozens of its analogues.
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
Gold-catalyzed oxidative cyclizations of 2-oxiranyl-1-alkynylbenzenes for diastereoselective synthesis of highly substituted 2-hydroxyindanones
Chaudhuri, Rupsha,Liu, Rai-Shung
supporting information; experimental part, p. 2589 - 2592 (2011/12/01)
We report the gold-catalyzed oxidative cyclizations of 2-oxiranyl-1- alkynylbenzenes into highly substituted 2-hydroxyindanone frameworks bearing a tertiary alcohol. Such gold-catalyzed reactions comprise an initial internal redox reaction, sulfoxide oxidation of α-carbonyl gold-carbenoids, followed by gold-catalyzed formal ene reactions on the resulting diketone intermediates. Copyright
PtII-catalyzed synthesis of 9-oxabicyclo[3.3.1]nona-2,6-dienes from 2-alkynyl-1-carbonylbenzenes and allylsilanes by an allylation/annulation cascade
Bhunia, Sabyasachi,Wang, Kuo-Chang,Liu, Rai-Shung
supporting information; experimental part, p. 5063 - 5066 (2009/03/11)
(Chemical Equation Presented) Platinum is key: A new catalytic synthesis of 9-oxabicyclo[3.3.1]nona-2,6-dienes from readily available 2-alkynyl-1- carbonylbenzenes, allylsilanes, and water is reported (see scheme). This reaction sequence is proposed to proceed through a series of three reactions, including allylation of the carbonyl group, hydroalkoxylation of the alkyne, and a new eneoxonium annulation.
Gold-catalyzed waste-free generation and reaction of azomethine ylides: Internal redox/dipolar cycloaddition cascade
Yeom, Hyun-Suk,Lee, Ji-Eun,Shin, Seunghoon
supporting information; experimental part, p. 7040 - 7043 (2009/04/07)
(Chemical Equation Presented) High-octane synthesis: Azomethine ylides can be generated from an internal redox reaction of a nitrone-tethered alkyne under electrophilic metal catalysis (see scheme; M=metal). This novel and atom-economical generation of an azomethine ylide does not involve potentially explosive diazo derivatives. The azomethine ylide can participate in a dipolar cycloaddition cascade to provide an azabicyclo[3.2.1]octane.
