Results 21 to 30 of about 6,084 (222)

Path integral evaluation of equilibrium isotope effects [PDF]

, 2009
A general and rigorous methodology to compute the quantum equilibrium isotope effect is described. Unlike standard approaches, ours does not assume separability of rotational and vibrational motions and does not make the harmonic approximation for ...
Angus W. R., Chandler D., Cowan R. D., Feynman R., Jiří Vaníček, Redlich O., Tomáš Zimmermann, Vaníček J.   +7 more
core   +2 more sources

1,7-Sigmatropic rearrangement in 1,2-dihydro and 1,2,3,4-tetrahydroquinoline synthesis using marine sponge/H2C2O4 as a catalyst [PDF]

, 2015
Marine sponge/oxalic acid was found to be an efficient catalyst for the imino Diels–Alder reaction of synthesized N-aryl-substituted aldimines and various alkenes to provide 1,2-dihyro and 1,2,3,4-tetrahydro-quinolines using 1,7-sigmatropic rearrangement
Behfar, Abdol-azim, Heidary, Minoo, Mostoufi, Azar, Shushizadeh, Mohammad Reza   +3 more
core   +2 more sources

Synthesis of substituted 8H-benzo[h]pyrano[2,3-f]quinazolin-8-ones via photochemical 6π-electrocyclization of pyrimidines containing an allomaltol fragment

Beilstein Journal of Organic Chemistry, 2023
For the first time, we elaborated a method for the synthesis of pyrimidines containing an allomaltol unit. The suggested approach is based on the reaction of 2-(1-(dimethylamino)-3-oxo-3-arylprop-1-en-2-yl)-3-hydroxy-6-methyl-4H-pyran-4-ones with ...
Constantine V. Milyutin, Andrey N. Komogortsev, Boris V. Lichitsky, Mikhail E. Minyaev, Valeriya G. Melekhina   +4 more
doaj   +1 more source

Three applications of path integrals: equilibrium and kinetic isotope effects, and the temperature dependence of the rate constant of the [1,5] sigmatropic hydrogen shift in (Z)-1,3-pentadiene [PDF]

, 2010
Recent experiments have confirmed the importance of nuclear quantum effects even in large biomolecules at physiological temperature. Here we describe how the path integral formalism can be used to describe rigorously the nuclear quantum effects on ...
A Calhoun, A Kohen, A Warshel, A Warshel, A Warshel, A Warshel, BJ Berne, C Predescu, DC Clary, DM Ceperley, H Liu, HB Schlegel, J Basran, J Merrick, J Vaníček, J Vaníček, J Vaníček, J Wang, JA Barker, Jiří Vaníček, JK Hwang, KM Doll, L Masgrau, M Ceotto, M Herman, M Parrinello, MHM Olsson, MJ Frisch, MJS Dewar, N Gresh, R Iftimie, SCL Kamerlin, T Yamamoto, T Zimmermann, Tomáš Zimmermann, WH Miller, WR Roth, WV Doering, Y Zhao, YT Chang   +39 more
core   +2 more sources

Reactive organoallyl species generated from aryl halides and allene: allylation of alpha,beta-unsaturated aldehydes and cyclic ketones employing Pd/In transmetallation processes [PDF]

, 2008
Allylation of α,β-unsaturated aldehydes and cyclic ketones promoted by Pd/In transmetallation processes has been studied. The unsaturated aldehydes underwent regioselective 1,2-addition to afford secondary homoally alcohols.
Anwar, Araki, Araki, Araki, Araki, Brase, Cacchi, Chan, Cleghorn, Cleghorn, Cooper, Cooper, Cooper, Denmark, Dupont, Fontana, Gai, Gomez, Grigg, Han, Hirashita, Hopkins, Howell, Kang, Kimura, Kless, Knodler, Larock, Laura A.T. Cleghorn, Law, Lee, Li, Littke, Liu, Marshall, Milena Simic, Miles, Miura, Miyabe, Nakahara, Norsikian, Ohno, Pardoe, Parrill, Podlech, Quan, Ronald Grigg, Sole, Tamaru, Tang, Tietze, Tsuji, Vladimir Savic, Wang, Zanoni, Zanoni, Zhou   +56 more
core   +2 more sources

Propargyl Vinyl Ethers and Tertiary Skipped Diynes: Two Pluripotent Molecular Platforms for Diversity-Oriented Synthesis [PDF]

, 2016
During the last years, we have been involved in the development of a diversity-oriented synthetic strategy aimed at transforming simple, linear, and densely functionalized molecular platforms into collections of topologically diverse scaffolds ...
Cotos, Leandro, García-Tellado, Fernando, López-Tosco, Sara, Méndez-Abt, Gabriela, Tejedor, David   +4 more
core   +1 more source

SAM-dependent enzyme-catalysed pericyclic reactions in natural product biosynthesis. [PDF]

, 2017
Pericyclic reactions-which proceed in a concerted fashion through a cyclic transition state-are among the most powerful synthetic transformations used to make multiple regioselective and stereoselective carbon-carbon bonds.
Chen, Mengbin, Hai, Yang, Houk, KN, Liu, Fang, Ohashi, Masao, Sato, Michio, Tang, Man-Cheng, Tang, Yi, Watanabe, Kenji, Yang, Zhongyue   +9 more
core   +1 more source

Chiral terpene auxiliaries V: Synthesis of new chiral γ-hydroxyphosphine oxides derived from α-pinene

Beilstein Journal of Organic Chemistry, 2019
New chiral regioisomeric γ-hydroxyphosphine ligands were synthesized from α-pinene. The key transformation was the thermal [2,3]-sigmatropic rearrangement of allyldiphenylphosphinites, obtained from (1R,2R,4S,5R)-3-methyleneneoisoverbanol and (1R,2R,3R ...
Anna Kmieciak, Marek P. Krzemiński
doaj   +1 more source

Tandem Reactions Combining Diels-Alder Reactions with Sigmatropic Rearrangement Processes and their Use in Synthesis [PDF]

Synthesis, 1998
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Neuschütz, Klaus, Velker, Jörg, Neier, Reinhard   +2 more
openaire   +2 more sources

Propargyl Claisen rearrangement: Allene synthesis and beyond [PDF]

, 2016
The propargyl Claisen rearrangement is a known protocol to gain access to functionalized allenes through the [3,3]-sigmatropic transformation of propargyl vinyl ethers.
Cotos, Leandro, García-Tellado, Fernando, Méndez-Abt, Gabriela, Tejedor, David   +3 more
core   +1 more source