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Search for "relative reactivities" in Full Text gives 14 result(s) in Beilstein Journal of Organic Chemistry.
Comparison of glycosyl donors: a supramer approach
Beilstein J. Org. Chem. 2024, 20, 181–192, doi:10.3762/bjoc.20.18
- putative participation in stabilization [52][53] of the glycosyl cation. More importantly, in our opinion, this result indicates the existence of unexpected difficulties in the determination of relative reactivities of glycosyl donors (vide infra). Discussion It is generally believed that the molecular
- reporting the results of glycosylation [39][43][44][46]. For this reason, it seems quite natural to compare different glycosyl donors at identical concentrations. It is this approach that is used for the determination of relative reactivities of glycosyl donors (RRV values) [69][70][71] and glycosyl
Dienophilic reactivity of 2-phosphaindolizines: a conceptual DFT investigation
Beilstein J. Org. Chem. 2022, 18, 1217–1224, doi:10.3762/bjoc.18.127
- nucleophilicity (N) [25][26] indices are other useful descriptors that explain relative reactivities of molecules in chemical reactions [27]. The electrophilicity indices of 2-phosphaindolizines also decrease in the same order as observed on the basis of global hardness and electronic chemical potential
Bi-mediated allylation of aldehydes in [bmim][Br]: a mechanistic investigation
Beilstein J. Org. Chem. 2018, 14, 2198–2203, doi:10.3762/bjoc.14.193
- . However, at this point of time, we are unable to prove the relative reactivities of species I and II towards 1a in [bmim][Br]. In analogy to the report [38] describing I as the most active allylating species in water medium, we could only presume that I is also the most active species for the present
Comparative profiling of well-defined copper reagents and precursors for the trifluoromethylation of aryl iodides
Beilstein J. Org. Chem. 2017, 13, 2297–2303, doi:10.3762/bjoc.13.225
- employed directly or generated in situ from precursors by published reports. Relative reactivities were also found to highly dependent on the nature of the iodoarenes. Keywords: benchmarking; copper; fluorine; fluoroalkylation; trifluoromethylation; Introduction Selectively fluorinated molecules that
Symmetry-based approach to oligostilbenoids: Rapid entry to viniferifuran, shoreaphenol, malibatol A, and diptoindonesin G
Beilstein J. Org. Chem. 2016, 12, 2689–2693, doi:10.3762/bjoc.12.266
- natural oligostilbenoids guided us to design a modular synthetic approach to these molecules by utilizing a three-step sequence consisting of Sonogashira coupling, iodocyclization, and Suzuki coupling. During our synthesis, the relative reactivities of ester, aldehyde, and alkoxy groups on the same aryl
Hydrogenation of unactivated enamines to tertiary amines: rhodium complexes of fluorinated phosphines give marked improvements in catalytic activity
Beilstein J. Org. Chem. 2015, 11, 622–627, doi:10.3762/bjoc.11.70
- hydrogenation of enamines, as was shown above, enamine hydrogenation benefits from electron-poor ligands, so the hope was that the enamine hydrogenation would be competitive over limonene hydrogenation. In addition, this solvent enables us to study the relative reactivities of these C=C bonds, as well as
Weakly nucleophilic potassium aryltrifluoroborates in palladium-catalyzed Suzuki–Miyaura reactions: relative reactivity of K[4-RC6F4BF3] and the role of silver-assistance in acceleration of transmetallation
Beilstein J. Org. Chem. 2015, 11, 608–616, doi:10.3762/bjoc.11.68
- consumption of K[4-RC6F4BF3] and SEP of the respective 4-RC6F4 group does not show certain correlation. Conclusion 1. The relative reactivities of K[4-RC6F4BF3] in the Ag(I)-assisted Pd-catalyzed cross-coupling reactions with 3-IC6H4F, 4-IC6H4F, 4-IC6H4CH3 or 4-BrC6H4CH3 in the presence of P(t-Bu)3 or PPh3
Synthesis, characterization and initial evaluation of 5-nitro-1-(trifluoromethyl)-3H-1λ3,2-benziodaoxol-3-one
Beilstein J. Org. Chem. 2014, 10, 1–6, doi:10.3762/bjoc.10.1
- kinetics of both reagents in a model system were studied providing insights into their relative reactivities. To this end, the reaction of 2 and 3 with p-toluenesulfonic acid monohydrate to 4 and 5, respectively, was monitored in MeCN by means of 19F NMR spectroscopy (Figure 6). Limitations arose from the
3-Pyridinols and 5-pyrimidinols: Tailor-made for use in synergistic radical-trapping co-antioxidant systems
Beilstein J. Org. Chem. 2013, 9, 2781–2792, doi:10.3762/bjoc.9.313
- results provide an explanation for the significant differences in the radical scavenging activities of pyridinols bearing these substituents in recently reported cell-based assays [18]. To provide further insight into the relative reactivities of these compounds we also carried out measurements of kinh in
Utilizing the σ-complex stability for quantifying reactivity in nucleophilic substitution of aromatic fluorides
Beilstein J. Org. Chem. 2013, 9, 791–799, doi:10.3762/bjoc.9.90
- mechanistic steps for these systems [18]. In another, a simple numerical method based on a few reactivity parameters was used to predict the relative reactivities in the reaction between methoxide anion and a series of chlorofluorobenzene derivatives [19]. In two other articles, the authors studied the effect
A quantitative approach to nucleophilic organocatalysis
Beilstein J. Org. Chem. 2012, 8, 1458–1478, doi:10.3762/bjoc.8.166
- ], and Figure 28 compares the relative reactivities of O-methylated and deoxy-Breslow intermediates toward the bis-pyrrolidino-substituted benzhydrylium ion 18l. Comparison of the left and the central column shows that the O-methylated Breslow intermediates 55b and 59 are 102 times less reactive than
- ]. Relative reactivities of deoxy- and O-methylated Breslow intermediates [114]. Reactivity scales for electrophiles and nucleophiles relevant for organocatalytic reactions (references and further reactivity parameters: [4]). Acknowledgements We thank the Deutsche Forschungsgemeinschaft (Schwerpunktprogramm
Alkene selenenylation: A comprehensive analysis of relative reactivities, stereochemistry and asymmetric induction, and their comparisons with sulfenylation
Beilstein J. Org. Chem. 2011, 7, 744–758, doi:10.3762/bjoc.7.85
- Institute of Technology, Cambridge, MA 02139 10.3762/bjoc.7.85 Abstract A broad perspective of various factors influencing alkene selenenylation has been developed by concurrent detailed analysis of key experimental and theoretical data, such as asymmetric induction, stereochemistry, relative reactivities
- the degree of substitution on C=C or upon substituent electronic effects. Electronic and steric effects influencing asymmetric induction, stereochemistry, regiochemistry, and relative reactivities in the addition of PhSeOTf to alkenes are compared and contrasted with those of PhSCl. Keywords: alkene
- selenenylation; asymmetric synthesis; calculations; electronic effects; regioselectivity; relative reactivities; steric effects; Introduction Electrophilic addition to alkenes is one of the most fundamental, generalized, and versatile methods for selective functionalization of hydrocarbons [1]. Despite recent
Molecular rearrangements of superelectrophiles
Beilstein J. Org. Chem. 2011, 7, 346–363, doi:10.3762/bjoc.7.45
- described the reactions of azoxypyridines in sulfuric acid media. The relative reactivities of the α- and β-isomers 108 and 109 were correlated to stabilization of a developing cationic charge center (Scheme 23). Thus, the α-isomer 108 ionizes in 100% H2SO4 to give the tricationic species 110 and subsequent
β-Hydroxy carbocation intermediates in solvolyses of di- and tetra-hydronaphthalene substrates
Beilstein J. Org. Chem. 2010, 6, 1035–1042, doi:10.3762/bjoc.6.118
- double bonds (3). The purpose of the present study was to determine whether the same dependence on stereochemistry of a β-hydroxy group would be observed for solvolytic reactions. Our conclusion, that it is, is based on a comparison of measurements of absolute and relative reactivities of cis and trans
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