Photoionization of highly charged ions using an ECR ion source and undulator radiation

Photoionization of Xe4+ to Xe7+ ions was studied by combining an electron cyclotron resonance ion source with synchrotron radiation. Multiconfiguration Dirac-Fock calculations were performed to interpret the data. Many autoionization lines were measured and identified, resulting from excitation of a 4d electron into nf and np orbitals followed by Auger decay of the excited states. Continuum photoionization is negligible for the higher members of the isonuclear series.     

Sequential rhodium-catalyzed stereo- and regioselective addition of organoboron derivatives to the alkyl 4-hydroxy-2-alkynoates/lactonizaction reaction

The sequential rhodium-catalyzed addition/lactonization reaction of organoboron derivatives to alkyl 4-hydroxy-2-alkynoates would constitute a novel methodology for the synthesis of 4-aryl/heteroaryl/vinyl-2(5H)-furanones with an excellent control of the regio- and chemoselectivity. The role played by rhodium precatalyst, ligands, reaction medium, and the feature of organoboron derivatives has been explored.     

2HDM portal for singlet-doublet dark matter

We present an extensive analysis of a model in which the (Majorana) Dark Matter candidate is a mixture between a SU(2) singlet and two SU(2) doublets. This kind of setup takes the name of singlet-doublet model. We will investigate in detail an extension of this model in which the Dark Matter sector interactions with a 2-doublet Higgs sector enforcing the complementarity between Dark Matter phenomenology and searches of extra Higgs bosons.     

Acidic Deep Eutectic Solvents as Active Media for Sustainable Synthesis of Biindoles Starting from 2,2’-Diaminotolanes and Aldehydes

We describe an alternative and more sustainable method for the synthesis of 2,2’-disubstituted 3,3’-biindoles starting from 2,2’-diaminotolanes and (hetero)arylaldehydes. The key feature of the approach is the use of an acidic Deep Eutectic Solvent (DES) able to exploit a double activity, i. e., solvent and Brønsted Acid (BA) catalyst, avoiding the use of Volatile Organic Compounds (VOCs) as solvents and additional acid catalysts. By this way, we synthesized twenty-five biindoles, including eighteen new compounds. The reactions run quickly under mild conditions by microwave heating at 70 °C, with yields ranging from good to very good. The reaction scope is rather broad. The medium demonstrated to be reusable at least five times with only a slight reduction in yields. Based on experimental evidence and previous literature findings, a plausible mechanism is proposed.     

An alternative one-pot gold-catalyzed approach to the assembly of 11H-indolo[3,2-c]quinolines

A new one-pot approach was developed to construct the 11H-indolo[3,2-c]quinoline scaffold through a gold-catalysed reaction of 2-[(2-aminophenyl)ethynyl]phenylamine derivatives with aldehydes. The broad scope and the high regioselectivity of this new protocol as well as the mild and neutral reaction conditions make it a viable alternative to the previously reported procedures.     

Tandem imination/annulation of γ- and δ-ketoalkynes in the presence of ammonia/amines

In this account, we summarize the peculiar effects and advantages of gold, silver, and titanium dual role catalysis over the uncatalyzed tandem imination/annulation processes of γ- and δ-ketoalkynes.     

Palladium-catalyzed reaction of aryl iodides with tertiary propargylic amides.: Highly substituted allenes through a regioselective carbopalladation/β-NPd elimination reaction

The palladium-catalyzed reaction of aryl iodides with tertiary propargylic amides affords highly substituted allenes. Best results have been obtained by using Pd(OAc)₂, ⁿBu₃N, HCOOH, and ⁿBu₄NCl or LiCl in DME at 100 °C. The reaction is highly regioselective and the carbopalladation step is controlled by the strong directing effect of the tertiary amide group.     

Electrochemical-Induced Cascade Reaction of 2-Formyl Benzonitrile with Anilines: Synthesis of N-Aryl Isoindolinones

An electrochemical initiated tandem reaction of anilines with 2-formyl benzonitrile has been developed. Thus, unprecedented 3-N-aryl substituted isoindolinones have been conveniently achieved by constant current electrolysis in a divided cell using catalytic amount of electricity and supporting electrolyte and a Pt-cathode as working electrode. The origin of the electrochemical activation as well as the mechanism of the subsequent chemical cascade reactions have been investigated by DFT calculations.