54526-84-0Relevant articles and documents
Ruthenium-Catalyzed Oxidative Cross-Coupling Reaction of Activated Olefins with Vinyl Boronates for the Synthesis of (E, E)-1,3-Dienes
Dethe, Dattatraya H.,Beeralingappa, Nagabhushana C.,Uike, Amar
, p. 3444 - 3455 (2021/02/16)
An oxidative cross-coupling reaction between activated olefins and vinyl boronate derivatives has been developed for the highly stereoselective construction of synthetically useful (E,E)-1,3-dienes. The highlight of this reaction is that exclusive stereoselectivity (only E,E-isomer) was achieved from a base-free, ligand-free, and mild catalytic condition with a less expensive [RuCl2(p-cymene)]2 catalyst.
A bicyclo[4.2.0]octene-derived monomer provides completely linear alternating copolymers via alternating ring-opening metathesis polymerization (AROMP)
Tan, Li,Parker, Kathlyn A.,Sampson, Nicole S.
, p. 6572 - 6579 (2015/02/19)
Strained bicyclic carbomethoxy olefins were utilized as substrates in alternating ring-opening metathesis polymerization and found to provide low-dispersity polymers with novel backbones. The polymerization of methyl bicyclo[4.2.0]oct-7-ene-7-carboxylate with cyclohexene in the presence of the fast-initiating Grubbs catalyst (H2IMes)(3-Br-Pyr)2Cl2Ru = CHPh leads to a completely linear as well as alternating copolymer, as demonstrated by NMR spectroscopy, isotopic labeling, and gel permeation chromatography. In contrast, intramolecular chain-transfer reactions were observed with [5.2.0] and [3.2.0] bicyclic carbomethoxy olefins, although to a lesser extent than with the previously reported monocyclic cyclobutenecarboxylic ester monomers [Song, A.; Parker, K. A.; Sampson, N. S. J. Am. Chem. Soc. 2009, 131, 3444]. Inclusion of cyclohexyl rings fused to the copolymer backbone minimizes intramolecular chain-transfer reactions and provides a framework for creating alternating functionality in a one-step polymerization.
One-pot transformation of silyl enol ethers into 1,3-dienes: In situ generation of alkenyl nonaflates and subsequent Heck reactions - Scope and limitations
Lyapkalo, Ilya M.,Webel, Matthias,Reissig, Hans-Ulrich
, p. 3646 - 3658 (2007/10/03)
Palladium-catalysed reactions between methyl acrylate and the isolated alkenyl nonaflates 2a, 2d and 2e proceed without difficulties, furnishing the desired 1,3-dienes 3, 14 and 15 in good yields. The use of other alkenyl nonaflates and olefins in this Heck reaction was also examined. The main purpose of this study was the development of an in situ generation of the required alkenyl nonaflates 2 from the corresponding silyl enol ethers 1 and their one-pot transformation into 1,3-dienes. Thus, the previously described fluoride-promoted exchange of the trimethylsilyl substituent of typical enol ethers 1 for a nonafluorobutylsulfonyl group was directly combined with the palladium-catalysed coupling step. This sequence allowed the efficient transformation of a variety of silyl enol ethers 1 into highly substituted 1,3-dienes in a practical one-pot procedure. The scope and limitations, together with the chemo- and stereoselectivity, of this process are discussed. A particular intriguing example involves a one-pot synthesis of silyl enol ether 1j by means of a Diels-Alder reaction, subsequent nonaflation and a Heck reaction with tert-butyl acrylate, furnishing the highly functionalised 1,3-diene 30 in good overall yield. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
A short and convenient preparation of (E)-3-(1-cyclohexenyl)-2- propenoic acid using a palladium(II) complex-catalyzed olefination
Lai, Gaifa,McAllister, Timothy
, p. 409 - 413 (2007/10/03)
A convenient, three-step preparation of (E)-3-(1-cyclohexenyl)-2- propenoic acid (1) from cyclohexanone was developed, which exploited the palladium(II) complex-catalyzed olefination of the triflate 3 as a key step.
Total synthesis of (+)-himbacine and (+)-himbeline
Chackalamannil, Samuel,Davies, Robert J.,Wang, Yuguang,Asberom, Theodros,Doller, Dario,Wong, Jesse,Leone, Daria,McPhail, Andrew T.
, p. 1932 - 1940 (2007/10/03)
Himbacine (1), a complex piperidine alkaloid isolated from the bark of Australian magnolias, is a promising lead in Alzheimer's disease research due to its potent muscarinic receptor antagonist property. We have described here a highly efficient synthetic strategy that resulted in the total synthesis of himbacine (1) in about 10% overall yield and isohimbacine (1a), an unnatural isomer of himbacine, in 18% overall yield. The total synthesis of himbacine was initially approached using an intramolecular Diels-Alder reaction as the key step to generate intermediate 5 followed by a [3 + 2] cycloaddition with nitrone 4 to produce the isoxazolidine derivative 3. Methylation followed by catalytic reduction of 3 gave 12'-hydroxyhimbacine (20), which, upon dehydration, gave isohimbacine (1a) as the sole product. In an alternative approach, an all-encompassing intramolecular Diels-Alder reaction of an appropriately substituted tetraene derivative 31, which bears the entire latent carbon framework and functional group substitution of himbacine, gave the desired advanced tricyclic intermediate 33, which was readily converted to (+)-himbeline (2) and (+)-himbacine (1).
The use of vicinal twofold Heck reaction products in diastereoselective sequential Michael additions - A convenient access to enantiomerically pure six-ring anellated cispentacin derivatives
Voigt, Katharina,Lansky, Annegret,Noltemeyer, Mathias,De Meijere, Armin
, p. 899 - 911 (2007/10/03)
The palladium-catalyzed coupling reactions of various acrylic acid derivatives 2a-e (e.g. methyl, tert-butyl, benzyl, menthyl esters) with 1,2-dibromobenzene (1), 1,2,3-tribromobenzene (4) and 1,2-dibromocyclohexene (6) yielded the correspondingly substit
On the Regioselectivity and Stereoselectivity of the Carbene Transfer from Fischer Carbene Complexes to Trisubstituted Electron-Deficient 1,3-Dienes
Buchert, Matthias,Hoffmann, Matthias,Reissig, Hans-Ulrich
, p. 605 - 614 (2007/10/02)
Thermal reactions of Fischer carbene complex 1 with trisubstituted electron-deficient 1,3-dienes 7, 8, 23, 25, 32, and 35 provided highly substituted vinylcyclopropanes in good yields.The carbene transfer proceeds highly regioselectively favouring cyclopropanation of the double bond not bearing the ester function.In addition, the diastereoselectivity is generally fairly high in preference of cyclopropanes with the methoxy group cis-positioned with respect to the olefin moiety.The reaction of methylcarbene complex 2 with diene ester 8 displays inversed regioselectivity.These ovservations are discussed together with solvent effects, and a mechanistic rationale is presented. - Key Words: Chromium complexes/ Carbene complexes/ 1,3-Dienes, electron-deficient/ Cycloadditions/ Vinylcyclopropanes, donor-acceptor-substituted/ Diastereoselectivity/ Regioselectivity
Synthesis of Dienoic Acids and Esters by Cationic Palladium Complex Catalyzed Carbonylation of Alkynols and Alkynediols
Huh, Keun-Tae,Orita, Akihiro,Alper, Howard
, p. 6956 - 6957 (2007/10/02)
The cationic palladium(II) aquo hydride, trans-(Cy3P)2Pd(H)(H2O)(+)BF4(-), is an excellent catalyst for the carbonylation of alkynols to dienoic acids and esters and of alkynediols to cross-conjugated diesters.
New C-C bond formation through the nickel-catalysed electrochemical coupling of 1,3-enynes and carbon dioxide
Derien, Sylvie,Clinet, Jean-Claude,Dunach, Elisabet,Perichon, Jacques
, p. 213 - 224 (2007/10/02)
A series of 1,3-enynes has been carboxylated in a nickel-catalysed electrochemical reaction carried out in a single-compartment cell fitted with a consumable magnesium anode.When 2,2'-bipyridine (bipy) or pentamethyldiethylene triamine (PMDTA) are added a
