Fe(II)/Et₃N-Relay-catalyzed domino reaction of isoxazoles with imidazolium salts in the synthesis of methyl 4-imidazolylpyrrole-2-carboxylates, its ylide and betaine derivatives

• Ekaterina E. Galenko,
• Olesya A. Tomashenko,
• Alexander F. Khlebnikov,
• Mikhail S. Novikov and
• Taras L. Panikorovskii

Beilstein J. Org. Chem. 2015, 11, 1732–1740, doi:10.3762/bjoc.11.189

• (Scheme 4). Ylide 2a was hydrolyzed with a lower yield due to the high solubility of the salt 14a in water. Betaines 6 can, in principle, exist in tautomeric equilibrium with the corresponding carboxy-substituted ylides 4 and N-heterocyclic carbenes 5. The results of the DFT study of the relative

An unusually stable chlorophosphite: What makes BIFOP–Cl so robust against hydrolysis?

• Roberto Blanco Trillo,
• Jörg M. Neudörfl and
• Bernd Goldfuss

Beilstein J. Org. Chem. 2015, 11, 313–322, doi:10.3762/bjoc.11.36

• . A DFT study of the hydrolysis in BIFOP–Cl verifies a higher repulsive interaction to water and a decreased leaving tendency of the chloride nucleofuge, which is caused by the fenchane units. This high stability of BIFOP–Cl against nucleophiles supports its application as a chiral ligand, for example

Comparing kinetic profiles between bifunctional and binary type of Zn(salen)-based catalysts for organic carbonate formation

• Carmen Martín and
• Arjan W. Kleij

Beilstein J. Org. Chem. 2014, 10, 1817–1825, doi:10.3762/bjoc.10.191

• ) complexes in conjunction with NBu4I for CO2/epoxide coupling reactions [26][27][28][29], proposing for this process the monometallic mechanism depicted in Scheme 2 [26]. Furthermore, a detailed DFT study for this transformation was reported supporting this proposed mechanism [36]. In the catalytic cycle of

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

• can be further advanced by kinetic studies and the isolation and characterization of key intermediates. Keywords: alkyne; azide; Click; copper; CuAAC; DFT study; Huisgen–Meldal–Sharpless cycloaddition; kinetics; reaction mechanism; Introduction In 1893, Michael discovered a reaction between dimethyl

• ) complexes as calculated in a DFT study by Ahlquist and Fokin [125] (transition states with Cu–Cu distances of 2.54 Å for L = X = chloride and 2.64 Å for L = acetylide). They tested copper(I) acetate in the CuAAC model reaction of benzyl azide with phenylacetylene and reported an excellent performance of

Computational study of the rate constants and free energies of intramolecular radical addition to substituted anilines

• Andreas Gansäuer,
• Meriam Seddiqzai,
• Tobias Dahmen,
• Rebecca Sure and
• Stefan Grimme

Beilstein J. Org. Chem. 2013, 9, 1620–1629, doi:10.3762/bjoc.9.185

• are normally underestimated (in particular for radical species) with semi-local GGAs. We conducted a DFT study using the above mentioned state-of-the-art quantum chemical methods which are applied successfully to various thermochemical problems in our group since several years. This well established

Recent developments in gold-catalyzed cycloaddition reactions

• Fernando López and
• José L. Mascareñas

Beilstein J. Org. Chem. 2011, 7, 1075–1094, doi:10.3762/bjoc.7.124

• subsequent elimination process on the resulting intermediate II accounts for the formation of the naphthyl ketone products 2, which were isolated in good yields. More recently, in 2004, Straub and coworkers reported a DFT study on these cycloadditions that led them to propose a modification of the