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The controlled functionalization of a single fluorine in a CF3 group is difficult and rare. Photochemical C-F bond functionalization of the sp3-C-H bond in trifluorotoluene, PhCF3, is achieved using catalysts made from earth-abundant lanthanides, (CpMe4)2Ln(2-O-3,5- t Bu2-C6H2)(1-C{N(CH)2N(iPr)}) (Ln = La, Ce, Nd and Sm, CpMe4 = C5Me4H). The Ce complex is the most effective at mediating hydrodefluorination and defluoroalkylative coupling of PhCF3 with alkenes; addition of magnesium dialkyls enables catalytic C-F bond cleavage and C-C bond formation by all the complexes. Mechanistic experiments confirm the essential role of the Lewis acidic metal and support an inner-sphere mechanism of C-F activation. Computational studies agree that coordination of the C-F substrate is essential for C-F bond cleavage. The unexpected catalytic activity for all members is made possible by the light-absorbing ability of the redox non-innocent ligands. The results described herein underscore the importance of metal-ligand cooperativity, specifically the synergy between the metal and ligand in both light absorption and redox reactivity, in organometallic photocatalysis.

Starting from documents in archive (convent of Our Lady, Genazzano) and images (photo album by Carlo Galli in Italian Geographic Society, Rome) this paper analyzes texts regarding the devotion to Our Lady of Good Counsel in Shkoder and similar worship in Genazzano. The modification of the place identified as the first site of the image is investigated (according to the legend, the place of miraculous angelic departure in 1467): for prodigies reported up to XIXth century it was identified at the church of S. Mary Magdalene in Casena beyond the Buna river; since 1875 recognized at the current location on the opposite side. The cults are specified in this two places (in Casena, S. Mary Magdalene; in the ruins under the castle reused as foundation of the new sanctuary, Our Lady of Shkoder). [ABSTRACT FROM AUTHOR]

This paper evaluates the narration by Dominican friar Vincenzo Vannutelli (1841-1900) of a journey to Shkodra occurred in June 1885 (published in 1886) as an early direct witness on local Roma people; the historical romanì presence in Albania; the tolerant attitude of the Albanian majority towards the ethnic minority; the communist assimilation project; the notes of Italian travelers in the first half of XXth century; the value of the episodic and partly prejudicial testimony of the friar visiting Albania in search of the pristine site of the sanctuary of Our Lady of Good Counsel who met the local Roma people describing them according to prevailing racial categories from bibliography and current mentality. [ABSTRACT FROM AUTHOR]

This article, published in ChemCatChem, discusses the synthesis of new diiron organometallic complexes with different properties. The complexes were found to have catalytic activity in hydroboration reactions, converting carbonyl compounds into organoboronates under mild conditions. The researchers highlight the importance of the diiron scaffold and the amino pendant of the hydrocarbyl ligand in this process. The article provides more detailed information on the synthesis and catalytic activity of these complexes. [Extracted from the article]

The author analyzes (in the perspective of ritual liminality) the iconography of the fragmentary frescoes found at the archeological site of the church in Derven (Kruja, uncovered in 2007 and lost in 2008). Once the scarcity of the apse's theme is verified (Deesis: Mary Kyriotissa and Child in her arms between Saints Peter and Paul), the author evaluates mid-fourteenth century stylistic comparisons in the Balkan area, as well as details of west-Adriatic influence. The proposed interpretation is linked to a progressive orientation of Albanian feudal lords towards Roman obedience, in light of the documents and the renewed worship of apostolic princes Peter and Paul's relics (holy heads) translated in 1369 in the papal cathedral of St. John Lateran in Rome. Pope Urban V promoted such worship - coinciding with the progressive return of the papal Holy See from Avignon to Rome - in an effort to strengthen the prestige of Petrine primacy. [ABSTRACT FROM AUTHOR]

A series of neutral and cationic rhodium complexes bearing IPr {IPr=1,3‐bis‐(2,6‐diisopropylphenyl)imidazolin‐2‐carbene} and π‐acceptor ligands are reported. Cationic species [Rh(η4‐cod)(IPr)(NCCH3)]+ and [Rh(CO)(IPr)(L)2]+ (L=pyridine, CH3CN) were obtained by chlorido abstraction in suitable complexes, whereas the cod‐CO derivative [Rh(η4‐cod)(IPr)(CO)]+ was formed by the carbonylation of [Rh(η4‐cod)(IPr)(NCCH3)]+. Alternatively, neutral derivatives of type RhCl(IPr)(L)2 {L=tBuNC or P(OMe)3} can be accessed from [Rh(μ‐Cl)(η2‐coe)(IPr)]2. In addition, the mononuclear species Rh(CN)(η4‐cod)(IPr) was prepared by cyanide‐chlorido anion exchange, which after carbonylation afforded the unusual trinuclear compound [Rh{1κC,2κN‐(CN)}(CO)(IPr)]3. Divergent catalytic outcomes in the phenylacetylene‐methanol transformations have been observed. Thus, enol ethers, arisen from hydroalkoxylation of the alkyne, were obtained with neutral Rh−CO catalyst precursors whereas dienol ethers were formed with cationic catalysts. Variable amounts of alkyne dimerization, cyclotrimerization or polymerization products were obtained in the absence of a strong π‐acceptor ligand on the catalyst. [ABSTRACT FROM AUTHOR]

Die Hydrothiolierung ungesättigter Kohlenstoff ‐ Kohlenstoff ‐ Bindungen ist eine praktische und atomökonomische Methode zum Einbau von Schwefel in organische Grundgerüste. In den letzten Jahren haben wir die Entwicklung einiger Übergangsmetallkatalysatoren zur Kontrolle von Regio ‐ und Stereoselektivität beobachtet. In diesem Kurzaufsatz beleuchten wir den mechanistischen Hintergrund dieser Transformation, um die Planung spezifischerer und aktiverer metallorganischer Hydrothiolierungskatalysatoren zu erleichtern. Balanceakt: In den letzten Jahren wurden Übergangsmetallkatalysatoren zur Kontrolle von Regio ‐ und Stereoselektivität bei der Hydrothiolierung ungesättigter Kohlenstoff ‐ Kohlenstoff ‐ Bindungen entwickelt. Um das Design wirksamerer Katalysatoren zu fördern, wird der komplexe mechanistische Hintergrund dieser Umwandlung beschrieben (siehe Abbildung). [ABSTRACT FROM AUTHOR]

The hydrothiolation of unsaturated carbon-carbon bonds is a practical and atom-economical approach for the incorporation of sulfur into organic frameworks. In recent years, we have witnessed the development of a range of transition-metal-based catalytic systems for the control of the regio- and stereoselectivity. In this Minireview we highlight the mechanistic background behind this transformation so as to help the design of more specific and active organometallic hydrothiolation catalysts. [ABSTRACT FROM AUTHOR]

Abstract: The oxidation of benzothiophene (BTs) and dibenzothiophene (DBTs) derivatives, of model fuel (MF) and authentic diesel fuel (ADF) with homogeneous and heterogeneous rhenium catalysts and H2O2 has been studied to design an alternative environmentally benign oxidative desulfurization process (ODS), for oil industry. The quantitative conversion of both BTs and DBTs derivatives was obtained in several of the cases investigated, to afford the corresponding sulfones as the only recovered products in very high yield. Excellent results in terms of both conversion of substrates and yields of sulfones were also obtained during oxidation of MF and ADF. Heterogeneous rhenium catalysts were stable systems to be used for several runs without any appreciable reduction of reactivity and selectivity. [Copyright &y& Elsevier]