17595-86-7Relevant academic research and scientific papers
Fast Suzuki-Miyaura cross-coupling reaction with hexacationic triarylphosphine Bn-dendriphos as ligand
Snelders, Dennis J. M.,Kreiter, Robert,Firet, Judith J.,Van Koten, Gerard,Gebbink, Robertus J. M. Klein
, p. 262 - 266 (2008)
The application of hexa[(dimethylamino)-methyl]-functionalized triphenylphosphine (1) and its benzylammonium salt, Bn-Dendriphos (2), in the Suzuki-Miyaura cross-coupling of aryl bromides with arylboronic acids is described. The 3,5-bis[(benzyldimethylammonio)methyl] substitution pattern in 2 leads to a rate enhancement compared to both the non-ionic parent compound 1 and triphenylphospine (PPh3) itself. At the same time, the resulting catalytic species are stable towards palladium black formation, even at a phosphine/palladium ratio of 1. These observations are attributed to the presence of a total of six ammonium groups in the backbone of the phosphine ligand, which presumably leads to an unsaturated phosphine-palladium complex.
Immobilized boronic acid for Suzuki-Miyaura coupling: Application to the generation of pharmacologically relevant molecules
Martinez-Amezaga,Delpiccolo,Mata
, p. 34994 - 35003 (2017)
An synthetic strategy for the generation of a variety of biaryl and related derivatives, based on Suzuki-Miyaura coupling using immobilized boronic acid, is described. The importance of the methodology was demonstrated by its further application to biologically interesting compounds such as 4-biaryl-β-lactams, descripted as cholesterol absorption inhibitors and anti-MRSA active agents, neoflavonoids, imidazoles, isoxazolines, among others.
Effects of co-solvents on reactions run under micellar catalysis conditions
Gabriel, Christopher M.,Lee, Nicholas R.,Bigorne, Florence,Klumphu, Piyatida,Parmentier, Michael,Gallou, Fabrice,Lipshutz, Bruce H.
, p. 194 - 197 (2017)
The impact of varying percentages of an organic solvent added to reactions run in aqueous nanomicelles as the reaction medium has been investigated. Issues such as rates of reaction, percent conversion, and yield, as well as various practical aspects (e.g
Metal-Free Aryl Cross-Coupling Directed by Traceless Linkers
Haensch, Veit G.,Neuwirth, Toni,Steinmetzer, Johannes,Kloss, Florian,Beckert, Rainer,Gr?fe, Stefanie,Kupfer, Stephan,Hertweck, Christian
supporting information, p. 16068 - 16073 (2019/11/28)
The metal-free, highly selective synthesis of biaryls poses a major challenge in organic synthesis. The scope and mechanism of a promising new approach to (hetero)biaryls by the photochemical fusion of aryl substituents tethered to a traceless sulfonamide linker (photosplicing) are reported. Interrogating photosplicing with varying reaction conditions and comparison of diverse synthetic probes (40 examples, including a suite of heterocycles) showed that the reaction has a surprisingly broad scope and involves neither metals nor radicals. Quantum chemical calculations revealed that the C?C bond is formed by an intramolecular photochemical process that involves an excited singlet state and traversal of a five-membered transition state, and thus consistent ipso–ipso coupling results. These results demonstrate that photosplicing is a unique aryl cross-coupling method in the excited state that can be applied to synthesize a broad range of biaryls.
Molecular Design of Donor-Acceptor-Type Organic Photocatalysts for Metal-free Aromatic C?C Bond Formations under Visible Light
Wang, Lei,Byun, Jeehye,Li, Run,Huang, Wei,Zhang, Kai A. I.
, p. 4312 - 4318 (2018/10/02)
Metal-free and photocatalytic radical-mediated aromatic C?C bond formations offer a promising alternative pathway to the conventional transition metal-catalyzed cross-coupling reactions. However, the formation of aryl radicals from common precursors such as aryl halides is highly challenging due to their extremely high reductive potential. Here, we report a structural design strategy of donor-acceptor-type organic photocatalysts for visible light-driven C?C bond formations through the reductive dehalogenation of aryl halides. The reduction potential of the photocatalysts could be systematically aligned to be ?2.04 V vs. SCE via a simple heteroatom engineering of the donor-acceptor moieties. The high reductive potential of the molecular photocatalyst could reduce various aryl halides into aryl radicals to form the C?C bond with heteroarenes. The designability of the molecular photocatalyst further allowed the synthesis of a high LUMO (lowest unoccupied molecular orbital) polymer photocatalyst by a self-initiated free radical polymerization without compromising its LUMO level. (Figure presented.).
A Structure-Activity Relationship Study of Bitopic N 6-Substituted Adenosine Derivatives as Biased Adenosine A1 Receptor Agonists
Aurelio, Luigi,Baltos, Jo-Anne,Ford, Leigh,Nguyen, Anh T. N.,J?rg, Manuela,Devine, Shane M.,Valant, Celine,White, Paul J.,Christopoulos, Arthur,May, Lauren T.,Scammells, Peter J.
, p. 2087 - 2103 (2018/03/21)
The adenosine A1 receptor (A1AR) is a potential novel therapeutic target for myocardial ischemia-reperfusion injury. However, to date, clinical translation of prototypical A1AR agonists has been hindered due to dose limiting adverse effects. Recently, we demonstrated that the biased bitopic agonist 1, consisting of an adenosine pharmacophore linked to an allosteric moiety, could stimulate cardioprotective A1AR signaling in the absence of unwanted bradycardia. Therefore, this study aimed to investigate the structure-activity relationship of compound 1 biased agonism. A series of novel derivatives of 1 were synthesized and pharmacologically profiled. Modifications were made to the orthosteric adenosine pharmacophore, linker, and allosteric 2-amino-3-benzoylthiophene pharmacophore to probe the structure-activity relationships, particularly in terms of biased signaling, as well as A1AR activity and subtype selectivity. Collectively, our findings demonstrate that the allosteric moiety, particularly the 4-(trifluoromethyl)phenyl substituent of the thiophene scaffold, is important in conferring bitopic ligand bias at the A1AR.
CoIII-Catalyzed Isonitrile Insertion/Acyl Group Migration Between C?H and N?H bonds of Arylamides
Kalsi, Deepti,Barsu, Nagaraju,Sundararaju, Basker
supporting information, p. 2360 - 2364 (2018/02/22)
A general efficient and site-selective cobalt-catalyzed insertion of isonitrile into C?H and N?H bonds of arylamides through C?H bond activation and alcohol assisted intramolecular trans-amidation is demonstrated. This straightforward approach overcomes the limitation by the presence of strongly chelating groups. Isolation of CoIII-isonitrile complex B has been achieved for the first time to understand the reaction mechanism.
Mild-Base-Promoted Arylation of (Hetero)Arenes with Anilines
Monzón, Diego M.,Santos, Tanausú,Pinacho-Crisóstomo,Martín, Víctor S.,Carrillo, Romen
supporting information, p. 325 - 333 (2018/01/15)
Transition metal-free radical arylation of heteroarenes is achieved at room temperature by simply adding aqueous sodium carbonate to a solution of the corresponding heteroarene and arenediazonium salt, which can even be formed in situ. Such an easy, inexpensive and mild methodology has been optimized and applied to the expeditious modification of interesting molecular cores like naphthylimide or bisthienylcyclopentenes.
Insights into the Catalytic Activity of [Pd(NHC)(cin)Cl] (NHC=IPr, IPrCl, IPrBr) Complexes in the Suzuki–Miyaura Reaction
Izquierdo, Frédéric,Zinser, Caroline,Minenkov, Yury,Cordes, David B.,Slawin, Alexandra M. Z.,Cavallo, Luigi,Nahra, Fady,Cazin, Catherine S. J.,Nolan, Steven P.
, p. 601 - 611 (2017/12/26)
The influence of C4,5-halogenation on palladium N-heterocyclic carbene complexes and their activity in the Suzuki–Miyaura reaction were investigated. Two [Pd(NHC)(cin)Cl] complexes bearing IPrCl and IPrBr ligands (IPr=1,3-bis(2,6-diisopropyl-phenyl)imidazol-2-ylidene; cin=cinnamyl) were synthesized. After determining the electronic and steric properties of these ligands, their properties were compared to those of [Pd(IPr) (cin)Cl]. The three palladium complexes were studied by using DFT calculations to delineate their behavior in the activation step leading to the putative 12-electron active catalyst. Experimentally, their catalytic activity in the Suzuki–Miyaura reaction involving a wide range of coupling partners (30 entries) at low catalyst loading was studied.
Photo-oxidative Cross-Dehydrogenative Coupling-Type Reaction of Thiophenes with α-Position of Carbonyls Using a Catalytic Amount of Molecular Iodine
Sudo, Yusuke,Yamaguchi, Eiji,Itoh, Akichika
supporting information, p. 1610 - 1613 (2017/04/13)
A metal-free photo-oxidative intermolecular C-H/C-H coupling reaction of thiophenes is demonstrated with carbonyls using a catalytic amount of molecular iodine. In this system, molecular oxygen in the air acted as a terminal oxidant to regenerate molecular iodine. A mechanistic study was also performed.
