5101-44-0Relevant articles and documents
A Facile Construction of Bisheterocyclic Methane Scaffolds through Palladium-Catalyzed Domino Cyclization
Qi, Hongbo,Han, Kaiming,Chen, Shufeng
supporting information, p. 2699 - 2704 (2021/08/03)
A convenient palladium-catalyzed domino cyclization reaction for the construction of bis(benzofuranyl)methane scaffolds bearing an all-carbon quaternary center has been described. In the cascade process, one C(sp2)—O bond, two C(sp2)—C(sp3) bonds as well as two benzofuran rings are formed in a single synthetic sequence. The approach shows wide scope of substrates and good functional-group tolerance. Moreover, this methodology is successfully extended to the synthesis of benzofuranyl methyl chromane derivatives.
Copper-Catalyzed Tandem Cross-Coupling/[2 + 2] Cycloaddition of 1,6-Allenynes with Diazo Compounds to 3-Azabicyclo[5.2.0] Ring Systems
He, Min,Chen, Nuan,Zhou, Ting,Li, Qing,Li, Hongguang,Lang, Ming,Wang, Jian,Peng, Shiyong
supporting information, p. 9559 - 9563 (2019/11/21)
An unprecedented copper-catalyzed tandem cross-coupling/[2 + 2] cycloaddition of 1,6-allenynes with diazo compounds was reported, chemo- and regioselectively providing 3-azabicyclo[5.2.0] frameworks in moderate to excellent yields under mild reaction conditions. Moreover, the products readily convert to highly functionalized quinolines via oxidative radical rearrangement.
Catalytic Transformations of Alkynes into either α-Alkoxy or α-Aryl Enolates: Mannich Reactions by Cooperative Catalysis and Evidence for Nucleophile-Directed Chemoselectivity
Sahani, Rajkumar Lalji,Patil, Manoj D.,Wagh, Sachin Bhausaheb,Liu, Rai-Shung
supporting information, p. 14878 - 14882 (2018/10/15)
The catalytic formation of gold enolates from alkynes, nitrones, and nucleophiles is described, and their Mannich reactions result in nucleophile-directed chemoselectivity through cooperative catalysis. For 1-alkyn-4-ols and 2-ethynylphenols, their gold-catalyzed nitrone oxidations afforded N-containing dihydrofuran-3(2H)-ones with syn selectivity. The mechanism involves the Mannich reactions of gold enolates with imines through an O-H-N hydrogen-bonding motif. For aryloxyethynes, their gold enolates react selectively with nitrones to deliver 3-alkylidenebenzofuran-2-ones, as controlled by a C-H-O hydrogen-bonding motif.
Ethynylphenyl carbonates and carbamates as dual-action acetylcholinesterase inhibitors and anti-inflammatory agents
Saxena, Jaya,Meloni, David,Huang, Mou-Tuan,Heck, Diane E.,Laskin, Jeffrey D.,Heindel, Ned D.,Young, Sherri C.
supporting information, p. 5609 - 5612 (2015/11/17)
Novel ethynylphenyl carbonates and carbamates containing carbon- and silicon-based choline mimics were synthesized from their respective phenol and aniline precursors and screened for anticholinesterase and anti-inflammatory activities. All molecules were micromolar inhibitors of acetylcholinesterase (AChE), with IC50s of 28-86 μM; the carbamates were two-fold more potent than the carbonates. Two of the most potent AChE inhibitors suppressed 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation by 40%. Furthermore, these molecules have physicochemical properties in the range of other CNS drugs. These molecules have the potential to treat inflammation; they could also dually target Alzheimer's disease through restoration of cholinergic balance and inflammation suppression.
Acetylenes from Aldehydes. Preparation of Ethynylphenols and Phenylacetylenes by Flash Vacuum Pyrolysis of Isoxazolones
Wentrup, Curt,Wiedenstritt, Maria,Winter, Hans-Wilhelm
, p. 1233 - 1236 (2015/08/18)
The flash vacuum pyrolysis method of synthesis of acetylenes from aldehydes via isoxazolones is a convenient method for the preparation of a variety of derivatives, including kinetically unstable, sensitive compounds such as the ethynylphenols.
Alkoxyboration: Ring-closing addition of B-O σ bonds across alkynes
Hirner, Joshua J.,Faizi, Darius J.,Blum, Suzanne A.
supporting information, p. 4740 - 4745 (2014/04/17)
For nearly 70 years, the addition of boron-X σ bonds to carbon-carbon multiple bonds has been employed in the preparation of organoboron reagents. However, the significantly higher strength of boron-oxygen bonds has thus far precluded their activation for addition, preventing a direct route to access a potentially valuable class of oxygen-containing organoboron reagents for divergent synthesis. We herein report the realization of an alkoxyboration reaction, the addition of boron-oxygen σ bonds to alkynes. Functionalized O-heterocyclic boronic acid derivatives are produced using this transformation, which is mild and exhibits broad functional group compatibility. Our results demonstrate activation of this boron-O σ bond using a gold catalysis strategy that is fundamentally different from that used previously for other boron addition reactions.
Cyclization of gold acetylides: Synthesis of vinyl sulfonates via gold vinylidene complexes
Bucher, Janina,Wurm, Thomas,Nalivela, Kumara Swamy,Rudolph, Matthias,Rominger, Frank,Hashmi, A. Stephen K.
, p. 3854 - 3858 (2014/05/06)
Differently substituted terminal alkynes that bear sulfonate leaving groups at an appropriate distance were converted in the presence of a propynyl gold(I) precatalyst. After initial formation of a gold acetylide, a cyclization takes place at the β-carbon atom of this species. Mechanistic studies support a mechanism that is related to that of dual gold-catalyzed reactions, but for the new substrates, only one gold atom is needed for substrate activation. After formation of a gold vinylidene complex, which forms a tight contact ion pair with the sulfonate leaving group, recombination of the two parts delivers vinyl sulfonates, which are valuable targets that can serve as precursors for cross-coupling reactions, for example. Gold vinylidene intermediates are generated by the cyclization of gold acetylides that carry a sulfonate leaving group. This result demonstrates for the first time that the formation of these species is not restricted to a dual activation mode. The cyclization products obtained herein contain a vinyl sulfonate moiety, which makes them useful building blocks for cross-coupling reactions.
Rational design of 4-aryl-1,2,3-triazoles for indoleamine 2,3-dioxygenase 1 inhibition
R?hrig, Ute F.,Majjigapu, Somi Reddy,Grosdidier, Aurélien,Bron, Sylvian,Stroobant, Vincent,Pilotte, Luc,Colau, Didier,Vogel, Pierre,Van Den Eynde, Beno?t J.,Zoete, Vincent,Michielin, Olivier
experimental part, p. 5270 - 5290 (2012/08/28)
Indoleamine 2,3-dioxygenase 1 (IDO1) is an important therapeutic target for the treatment of diseases such as cancer that involve pathological immune escape. Starting from the scaffold of our previously discovered IDO1 inhibitor 4-phenyl-1,2,3-triazole, we used computational structure-based methods to design more potent ligands. This approach yielded highly efficient low molecular weight inhibitors, the most active being of nanomolar potency both in an enzymatic and in a cellular assay, while showing no cellular toxicity and a high selectivity for IDO1 over tryptophan 2,3-dioxygenase (TDO). A quantitative structure-activity relationship based on the electrostatic ligand-protein interactions in the docked binding modes and on the quantum chemically derived charges of the triazole ring demonstrated a good explanatory power for the observed activities.
Dimerization of ethynylaniline to a quinoline derivative using a ruthenium/gold heterobimetallic catalyst
Shelton, Phillip A.,Hilliard, Casie R.,Swindling, Michael,McElwee-White, Lisa
scheme or table, p. 160 - 166 (2010/09/11)
Dimerization of 2-ethynylaniline in the presence of the Ru/Au complexes CpRu(PPh3)Cl(μ-dppm)AuCl or CpRu(PPh3)I(μ-dppm)AuI results in formation of a quinoline derivative. Monometallic model compounds for the Ru and Au centers did not catalyze the dimerization reaction. This transformation proceeds in higher yield in the absence of solvent.
Single bifunctional ruthenium catalyst for one-pot cyclization and hydration giving functionalized indoles and benzofurans
Nair, Reji N.,Lee, Paul J.,Rheingold, Arnold L.,Grotjahn, Douglas B.
supporting information; scheme or table, p. 7992 - 7995 (2010/09/18)
Chemical equation Presented Bifunctional is more than twice as fun! At low loading, catalyst 1 (see scheme) can form two important heterocycle classes, apparently by attack of XH on a vinylidene intermediate. Aza- and nitroindoles can be formed, and all N-protecting groups tested (alkyl, allyl, sulfonyl) were tolerated. The newly formed ring can be deuterated in one step, and for substrates with two terminal alkynes, cyclization can be followed by hydration, making this catalyst uniquely versatile.
