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Search for "reactive intermediate" in Full Text gives 64 result(s) in Beilstein Journal of Organic Chemistry.
Atherton–Todd reaction: mechanism, scope and applications
Beilstein J. Org. Chem. 2014, 10, 1166–1196, doi:10.3762/bjoc.10.117
- to prefer mechanism 2 (ii) because diethyl chlorophosphate 2 is a more reactive intermediate. After these pioneering works, the first investigation of the mechanism of the Atherton–Todd’s reaction was reported by Steinberg in 1950 [6]. In this work, the synthesis of dialkyl chlorophosphate 2 is
Preparation of phosphines through C–P bond formation
Beilstein J. Org. Chem. 2014, 10, 1064–1096, doi:10.3762/bjoc.10.106
- presence of K2CO3 or KOAc favored a good stereoselectivity in contrast to K3PO4 or DBU. Sodium hydride or Ag2CO3 promoted retention of configuration. The mechanism of the reaction was studied by Gaumont et al. through isolation of the reactive intermediate [174]. Lipshutz et al. reported the palladium
Flow microreactor synthesis in organo-fluorine chemistry
Beilstein J. Org. Chem. 2013, 9, 2793–2802, doi:10.3762/bjoc.9.314
- number of ciprofloxacin analogues in good overall yields with high purity. Reactions in which a reactive intermediate easily decomposes in batch reactors As aforementioned, the benefits of flow microreactor synthesis are 1) accurate control of reaction time, temperature, and pressure, 2) efficient mixing
Silica sulfuric acid: a reusable solid catalyst for one pot synthesis of densely substituted pyrrole-fused isocoumarins under solvent-free conditions
Beilstein J. Org. Chem. 2013, 9, 2344–2353, doi:10.3762/bjoc.9.269
- sulfonic group of SSA generates dehydrated cationic intermediate 9. This reactive intermediate 9 provokes a nucleophilic attack of primary amines to form bicyclo[3.3.0]octanamino compound 10. Then the α-hydroxy group of 10 attacks the adjacent carbonyl carbon to generate epoxy intermediate 11. This
The chemistry of amine radical cations produced by visible light photoredox catalysis
Beilstein J. Org. Chem. 2013, 9, 1977–2001, doi:10.3762/bjoc.9.234
- radical 134 concurrently. By carefully selecting reagents/conditions, either reactive intermediate can selectively participate in the designated reaction. As shown in Li and Wang’s work, iminium ion 133 is intercepted by nitroalkane to afford the aza-Henry product 135 while α-amino radical 134 is used to
- photoredox catalysis, new and innovative applications of this reactive intermediate will continue to develop. Amine radical cations’ mode of reactivity. Reductive quenching of photoexcited Ru complexes by Et3N. Photoredox aza-Henry reaction. Formation of iminium ions using BrCCl3 as stoichiometric oxidant
True and masked three-coordinate T-shaped platinum(II) intermediates
Beilstein J. Org. Chem. 2013, 9, 1352–1382, doi:10.3762/bjoc.9.153
- . described the synthesis of trans-[Pt(Np)(OTf)(PMe3)2] (Np = neopentyl) C1a. This compound reacts with benzene forming trans-[Pt(Ph)(OTf)(PMe3)2] C1b through a mechanism that involves trans-[Pt(Np)(PMe3)2]+ as a reactive intermediate [47]. The labile character of the coordinated triflate has been alleged to
Ring opening of 2-aza-3-borabicyclo[2.2.0]hex-5-ene, the Dewar form of 1,2-dihydro-1,2-azaborine: stepwise versus concerted mechanisms
Beilstein J. Org. Chem. 2013, 9, 761–766, doi:10.3762/bjoc.9.86
- isomerisation reaction, 22 kcal mol−1, should be high enough for an experimental observation in solution. However, in solution the dimerisation of 3 is computed to have a very low barrier (3 kcal mol−1), and thus 3 is expected to be a short-lived reactive intermediate. Keywords: ab initio; azaborine; BN
New reactive intermediates in organic chemistry
Beilstein J. Org. Chem. 2013, 9, 613–614, doi:10.3762/bjoc.9.67
- Gotz Bucher WestCHEM, School of Chemistry, University of Glasgow, Joseph-Black-Building, University Avenue, Glasgow G12 8QQ, United Kingdom 10.3762/bjoc.9.67 Keywords: reactive intermediates; Physical organic chemistry (POC) and reactive intermediate chemistry (RIC) belong to the core subjects
- studies. In order to characterise a reactive intermediate, it had to be trapped. Thus, in order to characterise a carbene, for example, one would intercept it with an alkene and isolate the resulting cyclopropane. Using internal quenchers (molecular clocks) providing well-defined competing reactions
- , product studies can even yield accurate values for the kinetics of intermolecular quenching reactions of reactive intermediates. More recent techniques to characterise reactive intermediates include matrix isolation spectroscopy, where a reactive intermediate is generated in a cryogenic noble-gas matrix
A computational study of base-catalyzed reactions of cyclic 1,2-diones: cyclobutane-1,2-dione
Beilstein J. Org. Chem. 2013, 9, 594–601, doi:10.3762/bjoc.9.64
- reaction appears to be the formation of 1-hydroxycyclopropane-1-carboxylate, which is corroborated by previous experimental observations. Keywords: ab initio; density functional; reactive intermediate; rearrangement; ring opening; Introduction Addition of nucleophiles, e.g., OH–, to 1,2-dicarbonyl
Complete σ* intramolecular aromatic hydroxylation mechanism through O2 activation by a Schiff base macrocyclic dicopper(I) complex
Beilstein J. Org. Chem. 2013, 9, 585–593, doi:10.3762/bjoc.9.63
- comparison, to broaden the scope of this study, in Figure 6 the study of a different mechanism starting from species b was envisaged. Intermediate l represents a valid option as a potential reactive intermediate for the direct attack to the aromatic ring by one of the oxygen atoms. The formation of l
Asymmetric desymmetrization of meso-diols by C2-symmetric chiral 4-pyrrolidinopyridines
Beilstein J. Org. Chem. 2012, 8, 1778–1787, doi:10.3762/bjoc.8.203
- and the substrate. A possible model for the transition state assembly for the enantioselective acylation of meso-1,2-cyclohexanediol (5) catalyzed by 11 is shown in Figure 2. A chiral acylpyridinium ion generated from 11 and isobutyric anhydride is expected to be the reactive intermediate which is
The role of silver additives in gold-mediated C–H functionalisation
Beilstein J. Org. Chem. 2011, 7, 892–896, doi:10.3762/bjoc.7.102
- reactive intermediate 3 [Au(OPiv)(IPr)] (OPiv = (CH3)3CCO2) (Figure 1). To verify this hypothesis, the well-defined complex [19] was used in test reactions following the earlier conditions. Complex 3 reacted with 2 in conjunction with Ag2O and gave complete conversion to 4 [Au(C6H2F3)(IPr)]. This strongly
Anion–π interactions influence pKa values
Beilstein J. Org. Chem. 2011, 7, 320–328, doi:10.3762/bjoc.7.42
- , primarily by modifying the rate. In these cases, interactions with the reactive intermediate or with the starting material can serve to accelerate a process, for example, by stabilisation of the intermediate or by activation of the starting material, or decelerate it in an analogous fashion. In restricted
Acid- mediated reactions under microfluidic conditions: A new strategy for practical synthesis of biofunctional natural products
Beilstein J. Org. Chem. 2009, 5, No. 40, doi:10.3762/bjoc.5.40
- acids is critical especially for the “fast” reactions to be successful. Such a common feature might be due to the integration of all favorable aspects of microfluidic conditions, i.e., efficient mixing, precise temperature control, and the easy handling of the reactive intermediate by controlling the
- temperature control, and the easy handling of the reactive intermediate by controlling the residence time. As can be seen from the three examples cited in this review, rapid determination of the reaction conditions is another aspect of using the microfluidic conditions in a combinatorial fashion. The
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