Electro-conversion of cumene into acetophenone using boron-doped diamond electrodes

• Mana Kitano,
• Tsuyoshi Saitoh,
• Shigeru Nishiyama,
• Yasuaki Einaga and
• Takashi Yamamoto

Beilstein J. Org. Chem. 2022, 18, 1154–1158, doi:10.3762/bjoc.18.119

• . Therefore, we treated 1 with KO2 and 18-crown-6 to examine whether the reaction proceeds only with the superoxide. As a result, only the starting material, 1, was recovered, which indicates that 3 is produced by a concerted reaction of the direct oxidation of 1 on the anode and the reduction of dissolved

Transient and intermediate carbocations in ruthenium tetroxide oxidation of saturated rings

• Manuel Pedrón,
• Laura Legnani,
• Maria-Assunta Chiacchio,
• Pierluigi Caramella,
• Tomás Tejero and
• Pedro Merino

Beilstein J. Org. Chem. 2019, 15, 1552–1562, doi:10.3762/bjoc.15.158

• for cyclopentane TS1 showed a typical geometry for an asynchronous concerted reaction (Figure 1) in agreement with that observed in the previous study carried out at the B3LYP/6-31G(d) level of theory with implicit MeCN solvent [25]. In that study, the forming/breaking bond distances (estimated for

• by a mesomeric effect of the α-heteroatom. Nevertheless, the corresponding IRCs for the three transition structures confirmed a concerted reaction connecting the corresponding encounter pairs EP1, EP2 and EP3 (see Supporting Information File 1), formed from reagents R1–3 and ruthenium(IV) tetroxide

Cationic cobalt-catalyzed [1,3]-rearrangement of N-alkoxycarbonyloxyanilines

• Itaru Nakamura,
• Mao Owada,
• Takeru Jo and
• Masahiro Terada

Beilstein J. Org. Chem. 2018, 14, 1972–1979, doi:10.3762/bjoc.14.172

• catalyst; concerted reaction; N–O bond; rearrangement; Introduction The 2-aminophenol moiety is ubiquitously found as a core structure of biologically active compounds, such as tigecycline [1], iguratimod [2], and phosalone (Scheme 1) [3]. The scaffolds have also been frequently utilized as synthetic

Phosphodiester models for cleavage of nucleic acids

• Satu Mikkola,
• Tuomas Lönnberg and
• Harri Lönnberg

Beilstein J. Org. Chem. 2018, 14, 803–837, doi:10.3762/bjoc.14.68

Are boat transition states likely to occur in Cope rearrangements? A DFT study of the biogenesis of germacranes

• José Enrique Barquera-Lozada and
• Gabriel Cuevas

Beilstein J. Org. Chem. 2017, 13, 1969–1976, doi:10.3762/bjoc.13.192

• elemanes formed via a Cope rearrangement from germacranolides only depends on the configuration of the most stable germacrane conformer since it is mainly a concerted reaction [15][18][33]. It is accepted that the conformers that normally carry out a Cope rearrangement are the ones that have crossed double

Recent advances in C(sp³)–H bond functionalization via metal–carbene insertions

• Bo Wang,
• Di Qiu,
• Yan Zhang and
• Jianbo Wang

Beilstein J. Org. Chem. 2016, 12, 796–804, doi:10.3762/bjoc.12.78

• over the decades [1][2][3][4][5][6][7][8]. Mechanistically, the C(sp3)–H bond insertion reaction is considered to follow a concerted reaction pathway with a three-center two electron transition state (Scheme 1). Since late transition metals, typically Rh(II) complexes, are most commonly employed as the

Strecker degradation of amino acids promoted by a camphor-derived sulfonamide

• M. Fernanda N. N. Carvalho,
• M. João Ferreira,
• Ana S. O. Knittel,
• Maria da Conceição Oliveira,
• João Costa Pessoa,
• Rudolf Herrmann and
• Gabriele Wagner

Beilstein J. Org. Chem. 2016, 12, 732–744, doi:10.3762/bjoc.12.73

• occurs before the TS in both cases. In contrast to these concerted reaction mechanisms, the decarboxylation of the zwitterions 5 and 6 appears to have a very low or near to zero activation barrier and is likely to dominate the reaction pattern. We therefore looked more closely to the products of the

Recent advances in the electrochemical construction of heterocycles

• Robert Francke

Beilstein J. Org. Chem. 2014, 10, 2858–2873, doi:10.3762/bjoc.10.303

• , yielding either the cis- or trans-cycloadduct exclusively. Consistent with the results of computational studies conducted by the authors, this stereospecifity points towards a concerted reaction mechanism. In contrast, cycloaddition of phenyl-substituted olefins seems to proceed via a stepwise mechanism

Aza-Diels–Alder reaction between N-aryl-1-oxo-1H-isoindolium ions and tert-enamides: Steric effects on reaction outcome

• Amitabh Jha,
• Ting-Yi Chou,
• Zainab ALJaroudi,
• Bobby D. Ellis and
• T. Stanley Cameron

Beilstein J. Org. Chem. 2014, 10, 848–857, doi:10.3762/bjoc.10.81

• ions – the cisoid conformation where the substituent at position 2 is at the vicinity of the carbonyl group is the one that can produce the electrocyclic (or non-concerted) reaction product(s). These cisoid conformations for N-(2-fluorophenyl) and N-(2-ethylphenyl) substituted 1-oxo-1H-isoindolium ions

Advancements in the mechanistic understanding of the copper-catalyzed azide–alkyne cycloaddition

• Regina Berg and
• Bernd F. Straub

Beilstein J. Org. Chem. 2013, 9, 2715–2750, doi:10.3762/bjoc.9.308

The rapid generation of isothiocyanates in flow

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 1613–1619, doi:10.3762/bjoc.9.184

• -chiral chloroximes the desired isothiocyanate product was correspondingly isolated as a single isomer (by 1H NMR) suggesting a concerted reaction pathway to be in operation. Importantly, more complex substrates (i.e. N-chloropyrrolidines, Table 2, entries 13–15) can be subjected to the reaction

Utilizing the σ-complex stability for quantifying reactivity in nucleophilic substitution of aromatic fluorides

• Magnus Liljenberg,
• Tore Brinck,
• Tobias Rein and
• Mats Svensson

Beilstein J. Org. Chem. 2013, 9, 791–799, doi:10.3762/bjoc.9.90

• hydrogen bonds from the NH2-group, and that the proton transfer to form HF takes place late in the concerted reaction step going from the σ-complex via TS2 to the products. An analysis of the energy differences between the three stationary points shows that the potential energy surface is extremely flat in

• that the B3LYP functional predicts a concerted reaction in some cases, including an intramolecular SNAr reaction, where the M06-2X functional and high level ab initio theory show that the reaction is stepwise [33]. In light of these observations, we investigated the potential energy surface also at the

Molecular rearrangements of superelectrophiles

• Douglas A. Klumpp

Beilstein J. Org. Chem. 2011, 7, 346–363, doi:10.3762/bjoc.7.45

• several routes: by dehydration of 160 with formation of the gitionic superelectrophile 161 and hydride shift/proton loss; by a concerted reaction involving loss of hydronium ion and hydride shift via 163; dehydration and proton loss with isomerization of the monocationic species 164. A similar conversion