Results 31 to 40 of about 31,425 (239)
Evolution of design approaches in asymmetric organocatalysis over the last decade
Tetrahedron Chem, 2023 This perspective intends to cover the vast field of asymmetric organocatalysis and its evolution during the last ten years. This work has evaluated the corresponding timeline of the progression of the field concerning the main synthetic approaches as ...
Nika Melnyk +3 more
doaj
Experimental and Theoretical Evidence for Nitrogen-Fluorine Halogen Bonding in Silver-Initiated Radical Fluorinations [PDF]
, 2019 We report experimental and computational evidence for nitrogen–fluorine halogen bonding in Ag(I)-initiated radical C–H fluorinations. Simple pyridines form [N–F–N]+ halogen bonds with Selectfluor to facilitate single-electron reduction by catalytic Ag ...
Baker, Sarah I +4 more
core +5 more sources
Magnetic nanoparticle-supported organocatalysis
Green Processing and Synthesis, 2013 Magnetic nanoparticle (MNP)-supported catalysis is a new method to facilitate catalyst separation and reuse. This technique has recently been introduced for organocatalysis.
Huang Yibo, Zhang Wei
doaj +1 more source
Enantioselective Organocatalytic Diels-Alder Trapping of Photochemically Generated Hydroxy-o-Quinodimethanes [PDF]
, 2016 The photoenolization/Diels-Alder strategy offers straightforward access to synthetically valuable benzannulated carbocyclic products. This historical light-triggered process has never before succumbed to efforts to develop an enantioselective catalytic ...
Cuadros, Sara +3 more
core +2 more sources
Cinchona Alkaloid-Catalyzed Asymmetric Conjugate Additions: The Bifunctional Brønsted Acid-Hydrogen Bonding Model. [PDF]
, 2016 Wynberg's report from 1977 that natural cinchona alkaloids catalyze the asymmetric conjugate addition of aromatic thiols to cycloalkenones is a landmark discovery in hydrogen bonding organocatalysis.
Grayson, Matthew N, Houk, KN
core +3 more sources
Asymmetric Orbifold Models of Non-supersymmetric Heterotic Strings [PDF]
Prog.Theor.Phys.95:249-257,1996, 1995 We investigate asymmetric orbifold models constructed from non-supersymmetric heterotic strings. We systematically classify the asymmetric orbifold models with standard embeddings and present a list of asymmetric orbifolds which are geometrically interpreted as toroidal compactifications of non-supersymmetric heterotic strings. By studying non-standard
arxiv +1 more source
Molecules, 2019 Chirality is one of the most important attributes for its presence in a vast majority of bioactive natural products and pharmaceuticals. Asymmetric organocatalysis methods have emerged as a powerful methodology for the construction of highly ...
Zhonglei Wang
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Asymmetric additions to dienes catalysed by a dithiophosphoric acid. [PDF]
, 2011 Chiral Brønsted acids (proton donors) have been shown to facilitate a broad range of asymmetric chemical transformations under catalytic conditions without requiring additional toxic or expensive metals.
Hamilton, Gregory +4 more
core +2 more sources
Stabilizing spiral structures in the asymmetric May-Leonard model [PDF]
Eur. Phys. J. B 94 (2021) 175, 2021 We study the induction and stabilization of spiral structures for the cyclic three-species stochastic May-Leonard model with asymmetric predation rates on a spatially inhomogeneous two-dimensional toroidal lattice using Monte Carlo simulations. In an isolated setting, strongly asymmetric predation rates lead to rapid extinction from coexistence of all ...
arxiv +1 more source
Design, synthesis, and evaluation of chiral thiophosphorus acids as organocatalysts
Beilstein Journal of Organic Chemistry, 2022 A series of P-stereogenic chiral phosphorus acids (CPAs) were synthesized to determine the requirements for efficient asymmetric organocatalysis. In order to eliminate the need for C2-symmetry in common CPAs, various scaffolds containing C1-symmetrical ...
Karen R. Winters, Jean-Luc Montchamp
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