102,213 research outputs found
Reactions of a phosphinito bridged diplatinum(I) complex with coinage metal electrophiles
No full textWe have recently described the synthesis of the complex
[(PHCy2)Pt1(m-PCy2){k2P,O-m-P(O)Cy2}Pt2(PHCy2)] (Pt-Pt)
(1), the first unsymmetrical phosphinito bridged Pt(I) species.[1]
The phosphinito bridge differentiates the charge distributions on
the two platinum atoms as confirmed by NMR spectroscopy
(dPt(1) = -4798 ppm, dPt(2) = -5207 ppm) and DFT studies. Complex
1 shows a rich chemistry as it reacts with nucleophiles [PHCy2,
PCy3, P(S)HCy2],[2] protic species HX [P(OH)Cy2, PhSH, HF,
HCl, HBr, HI, HBF4],[3, 4] and small molecules such as H2.[5]
Recently, we started investigations on the reactivity of complex 1
towards Au and Ag based electrophiles.
In this communication, it will be shown that, differently
from the isolobal H+ (which attacks the phosphinito oxygen and
migrates onto the Pt-Pt bond),3 the [Ag(PPh3)]+ electrophile
attacks complex 1 selectively to the Pt2-mP bond to afford the
cationic cluster [(PHCy2)Pt1(m-PCy2){k2P,O-m-P(O)Cy2}Pt2{m-
-Ag(PPh3)}(PHCy2)]+ (Pt–Pt) (2+) in which the [Ag(PPh3)]+
moiety bridges the mP-Pt2 bond. Analogous reactivity is observed
also when phosphane free electrophiles such as AgOTf, AgBF4,
AgClO4 and AgCl are used. Moreover, the reactivity of 1 towards
Au(I) electrophiles such as AuCl and [Au(PPh3)Cl] was dependent
on the reagent and on the experimental conditions.
references:
1. Gallo, V.; Latronico, M.; Mastrorilli, P.; Nobile, C. F.;
Suranna, G. P.; Ciccarella, G.; Englert, U.; Eur. J. Inorg.
Chem., 2005, 4607–4616.
2. Gallo, V.; Latronico, M.; Mastrorilli, P.; Nobile, C. F.;
Polini, F.; Re, N.; Englert, U.; Inorg. Chem., 2008, 47,
4785–4795.
3. Latronico, M.; Polini, F.; Gallo, V.; Mastrorilli, P;
Calmuschi-Cula B.; Englert, U.; Re, N.; Repo T.,
Raisanen M.; Inorg. Chem., 2008, 47, 9979-9796.
4. M. Latronico, P. Mastrorilli, V. Gallo, M.M.Dell’Anna,
F. Creati, N. Re, U. Englert, Inorg. Chem. 2011, 50,
3539–3558
5. Mastrorilli P., Latronico M., Gallo V., Polini F., Re N.,
Marrone A., Gobetto R., Ellena S.. J. Am. Chem. Soc.
2010, 132, 4752–476
Synthesis and activity of -Fe2O3 nanoparticles in the catalytic reduction of halonitroarenes under sustainable conditions
No full textAbstract.
The catalytic reduction of nitroarenes towards anilines is an important reaction from both academic
and industrial points of view, being the resulting products important intermediates to produce dyes,
agrochemicals, pigments, and pharmaceuticals. In addition, removal of nitroarene pollutants from
water by reducing them into anilines is a valuable method to purify contaminated matrices. Such
reductive reactions are frequently carried out by using noble metal catalysts [1], which are usually
very active and recyclable in some cases. Recently, the use of earth abundant metal catalysts has
gained great interest especially for economic reasons, as these materials are generally cheap and
easy to be reached [2]. In this framework, iron oxides catalysts are very attractive because they are
cheap and not toxic. Herein, we report on the synthesis of α-Fe2O3 nanoparticles (NPs) of size
ranging from 50 to 80 nm starting from a porous organic polymer (POP) containing Fe(III) sites,
which was in turn annealed at 400°C. The obtained NPs were characterized by SEM-EDX, XRPD,
IR and TXRF and were employed as active and recyclable catalysts in the reduction of p-bromonitrobenzene into p-bromo-aniline, using hydrazine hydrate in ethanol, taken as the model reaction.
[1] Dell’Anna, M.M.; Intini, S.; Romanazzi, G.; Rizzuti, A.; Leonelli, C.; Piccinni, F.; Mastrorilli,
P. J. Mol. Catal. A: Chem. 2014, 395, 307–314.
[2] Romanazzi, G.; Fiore, A.M.; Mali, M.; Rizzuti, A.; Leonelli, C.; Nacci, A.; Mastrorilli, P.;
Dell'Anna, M. M. Mol. Catal., 2018, 446, 31–3
Content and Functions of Social Sharing of Emotions: An Application of Multiple Correspondence Analysis
No full textNuovi criteri di selezione nella chirurgia laparoscopica del retto
No full textG. Benassai, L. Bucci, M. Gen ti le, M. Mazzeo, M. Mastrorilli, M. Santoro, L. Gaeta. Università degli Studi di Napoli Federico II - Facoltà di Medicina e Chirurgia - Cattedra di Chirurgia Generale Il (Dir.: Prof. F. Mazzeo )
La riduzione del trauma chirurgico trova una particolare indicazione sopratttto nel tratta mento della malattia diverticolare, dei volumi nosi adenomi e del carcinoma iniziale del co lon-retto. La riduzione dei tempi chirurgici ha quindi esteso le indicazioni ed ha aumentato il numero dei pazienti che si posssono candidare alla laparoscopia, sopranutto per i pazienti in età più avanzata. Abbiamo sottoposto a terapia chirurgica videoassistita 8 pazienti nel periodo 93-94, 5 di sesso femminile e 3 di sesso ma schile. L'età media è stata di 56 anni. 3 pa zienti sono stati operati per una patologia neo plastica del colon-retto, 2 per adenomi villosi del colon e 2 per malania diverticolare. Sono state confezionate 8 anastomosi, di cui 2 intra corporee. 2 pazienti sono stati, immediata mente riconvertiti durante il primo trattamento chirurgico per emostasi insufficiente e per la manifesta tensione dei capi anastomotici. Si sono verificate 2 deiscenze anastomotiche, di cui una in un paziente già riconvertito e tratta ta in via conservativa. un'altra, invece, in un paziente con peritonite saccata rioperato in 8° giornata. La chirurgia video-assistita offre, in dubbiamente, alcuni vantaggi qualora tutte le procedure non abbiano alcuna complicanza. Bisogna sottolineare che anche un’eventuale riduzione della degenza ospedaliera non può prescindere dai fisiologici tem pi di guarigione di un' anastomosi. L'estensione della linfecto mia rappresenta ancora un punto dibattuto. Nella nostra esperienza non abbiamo riscon trato sostanziali differenze nel numero dei linfonodi asportati anche se la piccola laparotomia potrebbe averci aiutato nel loro isola mento. In 2 casi abbiamo realizzato un'anasto mosi intracorporea, anche se l’asportazione del pezzo non è mai avvenuta per via trans anale. In definitiva, nel 37.5% dei casi siamo stati costretti a eseguire una laparotomia ampia dovendo ricorerre, tra questi, all'intervento di Hartrnann in un solo caso
How calcination affects the morphology and the catalytic activity of polymer supported Nickel
No full textA nickel containing monomer, Ni(AAEMA)2 (AAEMA = deprotonated form of 2-(acetoacetoxy) ethyl methacrylate) was co-polymerized with ethyl methacrylate (co-monomer) and ethylene glycol dimethacrylate (cross-linker) [1]. The obtained polymer was a green methacrylic resin containing Ni(II) centers homogeneously dispersed in the catalyst, which resulted insoluble in all common organic solvents and in water. The material can be described as an amphiphilic resin, air and moisture stable, with the peculiarity to swell in halogenated solvents, acetone and water and to shrink in diethyl ether and petroleum ether. The polymer was calcined under reductive conditions (dihydrogen with initial pressure of 5 bar) following two procedures, differing from each other for the cooling conditions. In the first procedure the calcined material was cooled under dihydrogen gas, while in the second one the cooling step occurred under air. After calcination, the green Ni(II) based co-polymer turned into black resins, Ni-res1 (obtained with hydrogen cooling) and Ni-res2 ((obtained with air cooling). TEM analyses showed that both Ni-res1 and Ni-res2 supported Ni nanoparticles with different morphologies, being the metal nanoparticles onto Ni-res1 smaller than the ones dispersed in Ni-res2, that had an urchin-like shape. Both Ni based co-polymers were tested as catalysts in the reduction of nitrobenzene with NaBH4 [2]. Ni-res1 resulted more active and selective towards aniline, with respect to Ni-res2.
[1] M.M. Dell’Anna, G. Romanazzi, P. Mastrorilli, Curr. Org. Chem. 17 (2013) 1236
[2] A.M. Fiore, G. Romanazzi, M.M. Dell’Anna, M. Latronico, C. Leonelli, A. Rizzuti, M. Mali, P. Mastrorilli, Mol. Catal. 476 (2019) 11050
Parlare delle emozioni degli altri. Due studi sulla condivisione sociale secondaria delle emozioni
No full text
- …
