57188-99-5Relevant academic research and scientific papers
Enantioselective Cyanosilylation of Alkynyl Ketones Catalyzed by Combined Systems Consisting of Chiral Ruthenium(II) Complex and Lithium Phenoxide
Ohkuma, Takeshi,Kurono, Nobuhito,Sakaguchi, Yusuke,Yamauchi, Kohei,Yurino, Taiga
supporting information, p. 1517 - 1522 (2018/02/28)
Asymmetric cyanosilylation of alkynyl ketones with the catalyst systems consisting of amino acid/2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (BINAP)/ruthenium(II) complex and lithium phenoxide (Ru?Li cat.) was studied. The reaction was conducted in tert-butyl methyl ether (TBME) at ?78 °C with a substrate-to-catalyst molar ratio (S/C) as high as 2000. A series of simple and functionalized ketones was converted into the alkynyl tertiary cyanohydrin derivatives in up to 99% ee. Appropriate selection of an amino-acid ligand of the catalyst according to the substrate structure was crucially important to achieve high enantioselectivity and a wide scope of substrates. Transformation of the chiral cyanohydrin product into a functionalized lactone was also examined. (Figure presented.).
COMPOUNDS, DEVICES, AND USES THEREOF
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Paragraph 00544, (2018/04/21)
The present invention provides compounds, e.g., compounds of Formula (I) and pharmaceutically acceptable salts, solvates, hydrates, tautomers, stereoisomers, isotopically labeled derivatives, and compositions thereof. Also provided are implantable elements (e.g., devices and materials) comprising the same, as well as methods of use thereof, e.g., for treating or preventing a disease, disorder, or condition.
Synthesis of Functionalized [3], [4], [5] and [6]Dendralenes through Palladium-Catalyzed Cross-Couplings of Substituted Allenoates
Lippincott, Daniel J.,Linstadt, Roscoe T. H.,Maser, Michael R.,Lipshutz, Bruce H.
supporting information, p. 847 - 850 (2017/01/14)
A mild method for the synthesis of highly functionalized [3]–[6]dendralenes is reported, representing a general strategy to diversely substituted higher homologues of the dendralenes. The methodology utilizes allenoates bearing various substitution patter
Mechanistic insights into the Pd-catalyzed direct amination of allyl alcohols: Evidence for an outer-sphere mechanism involving a palladium hydride intermediate
Sawadjoon, Supaporn,Sjoeberg, Per J. R.,Orthaber, Andreas,Matsson, Olle,Samec, Joseph S. M.
supporting information, p. 1520 - 1524 (2014/03/21)
The mechanism of direct amination of allyl alcohol by a palladium triphenylphosphite complex has been explored. Labelling studies show that the reaction proceeds through a π-allylpalladium intermediate. A second-order dependence of reaction rate on allyl alcohol concentration was observed. Kinetic isotope effect studies and ESI-MS studies are in agreement with a reaction proceeding through a palladium hydride intermediate in which both O-H bond and C-O bond cleavages are involved in rate-determining steps. A stereochemical study supports an outer-sphere nucleophilic attack of the π-allylpalladium intermediate giving complete chiral transfer from starting material to product. Two cleavages: The mechanism of the direct amination of allyl alcohol by palladium complexes bearing triphenylphosphite ligands has been explored. Kinetic isotope and ESI-MS studies are in good agreement with that both Oi￡H bond and Ci￡O bond cleavages are involved in rate-determining steps. Furthermore, stereochemical studies support an outer-sphere nucleophilic attack of the π-allylpalladium intermediate. Copyright
Ruthenium-catalyzed [2 + 2] cycloadditions between norbornene and propargylic alcohols or their derivatives
Tsui, Gavin C.,Villeneuve, Karine,Carlson, Emily,Tam, William
, p. 3847 - 3856 (2014/08/18)
Diastereoselective ruthenium-catalyzed [2 + 2] cycloadditions of norbornene and propargylic alcohols or their derivatives were investigated. The cycloadditions were found to be highly stereoselective, giving exo cycloadducts in moderate to excellent yields with diastereoselectivities up to 92:8. When a chiral propargylic alcohol was used in the cycloaddition, up to 80% ee of the [2 + 2] cycloadducts was observed after oxidation of the alcohol.
Synthesis of furans through silver-catalyzed propargyl-claisen rearrangement followed by cyclocondensation
Palisse, Adeline,Kirsch, Stefan F.
supporting information, p. 7095 - 7098 (2015/01/09)
The generation of highly substituted furans from propargyl vinyl ethers bearing a free hydroxy group was investigated. In the presence of catalytic amounts of AgBF4, a formal [3,3] sigmatropic rearrangement takes place in the first stage of the
Bifunctionalized allenes. Part XIII. A convenient and efficient method for regioselective synthesis of phosphorylated α-hydroxyallenes with protected and unprotected hydroxy group
Ismailov, Ismail E.,Ivanov, Ivaylo K.,Christov, Valerij C.
, p. 6309 - 6329 (2014/06/10)
The paper describes a convenient and efficient method for regioselective synthesis of phosphorylated α-hydroxyallenes using an atom economical [2,3]-sigmatropic rearrangement of intermediate propargyl phosphites or phosphinites. These can be readily prepared via reaction of protected alkynols with dimethyl chlorophosphite or chlorodiphenyl phosphine respectively in the presence of a base.
Establishing the concept of aza-[3 + 3] annulations using enones as a key expansion of this unified strategy in alkaloid synthesis
Gerasyuto, Aleksey I.,Ma, Zhi-Xiong,Buchanan, Grant S.,Hsung, Richard P.
supporting information, p. 1170 - 1178 (2013/07/26)
A successful enone version of an intramolecular aza-[3 + 3] annulation reaction is described here. Use of piperidinium trifluoroacetate salt as the catalyst and toluene as the solvent appears to be critical for a successful annulation. We also demonstrated for the first time that microwave irradiation can accelerate aza-[3 + 3] annulation reactions. An attempt to expand the scope of the enone aza-[3 + 3] annulation was made in the form of propyleine synthesis as a proof of concept. While synthesis of the enone annulation precursor was successfully accomplished, the annulation proved to be challenging and was only modestly successful.
Pd-catalyzed asymmetric synthesis of N-allenyl amides and their Au-catalyzed cycloisomerizative hydroalkylation: A new route toward enantioenriched pyrrolidones
Boutier, Audrey,Kammerer-Pentier, Claire,Krause, Norbert,Prestat, Guillaume,Poli, Giovanni
supporting information; experimental part, p. 3840 - 3844 (2012/06/15)
Palladium to make them, gold to cyclize them! Gold-catalyzed cycloisomerizative hydroalkylation of N-allenyl amides affords regioselectively 4-vinyl-γ-lactams. This transformation is stereospecific and takes place with a total axis-to-center chirality tra
Cationic rhodium(I) complex-catalyzed [3 + 2] and [2 + 1] cycloadditions of propargyl esters with electron-deficient alkynes and alkenes
Shibata, Yu,Noguchi, Keiichi,Tanaka, Ken
supporting information; experimental part, p. 7896 - 7898 (2010/08/05)
A cationic rhodium(I) complex, [Rh(cod)2]SbF6, catalyzes the [3 + 2] cycloaddition of propargyl esters with dialkyl acetylenedicarboxylates in good yields, presumably through carbonyl-stabilized cationic rhodium(I) alkenylcarbene intermediates. The same rhodium(I) complex also catalyzes the [2 + 1] cycloaddition (cyclopropanation) of propargyl esters with N,N-disubstituted acrylamides in good yields with perfect diastereoselectivity.
