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The direct metal-free borylation of diaryliodonium salts with diboron reagents is now demonstrated to be a feasible process toward formation of aryl boronic esters without any additive or catalysts, and it can be extended to a two-step C-C coupling of both aryl groups of the initial diaryliodonium reagent.

Novel membrane-free chemically modified polystyrene microspheres for the optical detection of sulphate in aqueous media are introduced. The working principle of this sensor is based on the surface mass-extraction equilibrium of the target species. This allows overcoming the strong hydration energy penalty, a typical problem for the detection of divalent anions. This optical sensor exhibits both enhanced sensitivity and selectivity, which allows the accurate detection of sulphate in biological samples. To illustrate these features the determination of sulphate in urine is presented.

The stereospecific hydrolysis of bulky aminophosphine boranes is reported for the first time. The resulting phosphinous acid boranes, upon activation, undergo stereospecific nucleophilic substitution reaction at the phosphorous center with amine nucleophiles. The combination of these two processes provides a novel access to bulky P*-ligands.

Using a purification method introduced earlier based on redox properties it was possible to isolate Sc3N@Ih-C80 and Sc3N@D3h-C78 and a mixture of Sc3N@D5h-C80 and Sc3N@D3-C68. Taking advantage of their chemical reactivity differences, Sc3N@D5h-C80 was isolated from Sc3N@D3-C68 followed by further functionalization, giving rise to five new methano-derivatives of Sc3N@D5h-C80.

Experimental and theoretical rationalization on regioselective mixed diboration of alkenes, with the unsymmetrical diboron reagent Bpin¿ Bdan, providing the protecting Bdan moiety in the internal position

author can archive pre-print (ie pre-refereeing). 12 meses de embargo DOI: 10.1039/c4cc02098g URL: http://pubs.rsc.org/en/Content/ArticleLanding/2014/CC/c4cc02098g#!divAbstract Filiació URV: SI Activated olefins directly react with phenylselenium boranes, at room temperature, without the need of metal or organocatalytic assistance. A simple mechanism that involves the interaction of the electron pair of carbonyl functional group in ¿,¿-unsaturated ketones and aldehydes, with the empty p orbital of the boron atom, justifies the efficient reaction towards the kinetically and thermodynamically most stable 1,4-addition product. Up to 12 examples of ¿ (phenylseleno) substituted ketones and aldehydes have been prepared with moderate to high yield. The simplicity and efficiency of this new reactivity generates new strategic platforms towards the C-Se bond formation and opens non existing pathways to create C-heteroatom bonds, as a general tool

author can archive pre-print (ie pre-refereeing). 12 meses de embargo DOI: 10.1039/c4cc02098g URL: http://pubs.rsc.org/en/Content/ArticleLanding/2014/CC/c4cc02098g#!divAbstract Filiació URV: SI Activated olefins directly react with phenylselenium boranes, at room temperature, without the need of metal or organocatalytic assistance. A simple mechanism that involves the interaction of the electron pair of carbonyl functional group in ¿,¿-unsaturated ketones and aldehydes, with the empty p orbital of the boron atom, justifies the efficient reaction towards the kinetically and thermodynamically most stable 1,4-addition product. Up to 12 examples of ¿ (phenylseleno) substituted ketones and aldehydes have been prepared with moderate to high yield. The simplicity and efficiency of this new reactivity generates new strategic platforms towards the C-Se bond formation and opens non existing pathways to create C-heteroatom bonds, as a general tool

The reaction of dienyl carbamates with PhI(OR)2 in the presence of rhodium catalysts affords vinyl aziridines which are in situ regio- and stereoselectively opened to afford oxyamination products resulting from a selective SN2 (Rh2(OAc)4/PhI(OPiv)2) or SN20 (Rh2(OPiv)4/PhI(OAc)2) opening. The scope and limitations of this tandem process are described.

Experimental and theoretical rationalization on regioselective mixed diboration of alkenes, with the unsymmetrical diboron reagent Bpin¿ Bdan, providing the protecting Bdan moiety in the internal position

The directmetal-free borylation of diaryliodoniumsalts with diboron reagents is now demonstrated to be a feasible process toward formation of aryl boronic esters without any additive or catalysts, and it can be extended to a two-step C¿C coupling of both aryl groups of the initial diaryliodonium reagent.

Filiació URV: SI The first intermolecular Pauson-Khand reaction conduct-ed with internal alkynylboronic esters has been described. This strategy allows the installation of the boronic ester moiety in ¿-position of the cyclopentenone with total re-gio- and stereoselectivity. More interestingly, the resulting adduct can be subsequently derivatized by Suzuki-Miyaura cross-coupling reaction allowing any combination of ¿,¿-disubstituted cyclopentenones, solving, thus, a well-known and long-standing drawback about regioselectivity in Pauson-Khand reaction

Well defined Ni nanoparticles (NiNPs) stabilized with N-heterocyclic carbenes (NHCs) have been synthesized through a new methodology involving the decarboxylation of a zwitterionic CO2 adduct. Their catalytic performance was tested in the partial hydrogenation of alkynes into (Z)-alkenes under very mild reaction conditions (50 8C and 5 bar H2 pressure), providing excellent activities and selectivities

Using a purification method introduced earlier based on redox properties it was possible to isolate Sc3N@Ih-C80 and Sc3N@D3h-C78 and a mixture of Sc3N@D5h-C80 and Sc3N@D3-C68. Taking advantage of their chemical reactivity differences, Sc3N@D5h-C80 was isolated from Sc3N@D3-C68 followed by further functionalization, giving rise to five new methano-derivatives of Sc3N@D5h-C80.

The first intermolecular Pauson¿Khand reaction, conducted using internal alkynylboronic esters, allows the installation of the boronic ester moiety at the b-position of the cyclopentenone with total regio- and stereoselectivity.

Novel membrane-free chemically modified polystyrene microspheres for the optical detection of sulphate in aqueous media are introduced. The working principle of this sensor, based on the surface mass-extraction of the target species, allows overcoming the strong hydration energy penalty, a typical problem for the detection of divalent anions. This optical sensor exhibits both, enhanced sensitivity and selectivity, which allows the accurate detection of sulphate biological samples. To illustrate these features, the determination of sulphate in urine is presented.