Evolution of Triangular All-Metal Aromatic Complexes from Bonding Quandaries to Powerful Catalytic Platforms.

This manuscript describes an overview on the literature detailing the observation of trinuclear complexes that present delocalized metal-metal bonds similar to those of regular aromatics, which are formed combining main group elements. A particular emphasis is given to the structural and electronic features of aromatic clusters that are sufficiently stable to allow their isolation. In parallel to the description of their key bonding properties, the work presents reported catalytic applications of these complexes, which already span from elaborated C-C-forming cascades to highly efficient cross-coupling methods.

[Integrated approach to the promotion of health and safety in agriculture: a pilot study in the Cremona area].

The agricultural sector in Cremona country is made up of many small farms and this makes it difficult to realease the principles of health and safety at work. In this experience an innovative platform for information and training, in which the agricoltural trade unions are privileged partner of public institutions in the road map for continuous improvement, has been tested. In a first phase, the availability of expert technicians to check the consistency of the application of safety standards has been offered by the trade associations free of charge to 100 farms.

Reactivity of the zwitterionic ligand EtNHC(S)Ph2P[double bond, length as m-dash]NPPh2C(S)NEt towards [Ru3(CO)12]. Sulfur transfer and ligand fragmentation leading to the methideylamide [-N(Et)-CH(R)-] micro3-bridging moiety.

The reaction of EtNHC(S)Ph2P[double bond, length as m-dash]NP+Ph2C(S)N(-)Et (HEtSNS) with [Ru3(CO)12] has been carried out under two different experimental conditions: in the first case [Ru3(CO)12], previously turned into the labile intermediate [Ru3(CO)10(CH3CN)2], afforded, at room temperature in dichloromethane, the trinuclear clusters [Ru3(CO)11(CNEt)] (1), [Ru3(CO)9(micro-H)[(micro-S:kappa-P)Ph2PN[double bond, length as m-dash]PPh2C(S)NEt]] (2), [Ru3(CO)9(micro-H)[(micro-S:kappa-P)Ph2PN[double bond, length as m-dash]P(S)Ph2]] (3) and [Ru3(CO)10[(micro-kappa2P)Ph2PNHPPh2]] (3). Ligand fragmentation occurs via loss of EtNC or EtNCS, without sulfur transfer to the cluster core. In the second case, [Ru3(CO)12] reacted with HEtSNS in toluene at 70 degrees C, giving the trinuclear clusters , [Ru3(CO)7(CNEt)(micro3-S)[(micro2-N:eta1-C:kappa1-P)Ph2PN[double bond, length as m-dash]PPh2C(H)NEt]] (6), [Ru3(CO)8)(micro3-S)[(micro2-N:eta-C:kappa-P)Ph2PN[double bond, length as m-dash]PPh2C(H)NEt]] (6) and [Ru3(CO)6(micro3-CO)(micro3-S)(EtNC)[(micro-kappa2P) Ph2PNHPPh2]] (7).

Zwitterionic metalates of group 11 elements and their use as metalloligands for the assembly of multizwitterionic clusters.

Reaction of RNHC(S)PPh2NPPh2C(S)NR (HRSNS; R = Me, Et) with M(I) (M = Cu, Ag, Au) salts afforded zwitterionic complexes of the general formula [M(RSNS)] (M = Cu, Ag, Au). The ligand was found in the solid state in S,S-kappa2 and S,N,S-kappa3 coordination fashions. [Cu(RSNS)] and [Ag(RSNS)] can be used as metalloligand building blocks for the assembly of pentanuclear multizwitterionic Cu5, Cu3Ag2 and Ag5 core clusters of the general formula [M'2{M(RSNS)}3]2+ (M = Cu, M' = Cu, Ag; M = M' = Ag) upon reaction with suitable M' salts.