A Journey from Thermally Tunable Synthesis to Spectroscopy of Phenylmethanimine in Gas Phase and Solution

Phenylmethanimine is an aromatic imine with a twofold relevance in chemistry: organic synthesis and astrochemistry. To tackle both aspects, a multidisciplinary strategy has been exploited and a new, easily accessible synthetic approach to generate stable imine-intermediates in the gas phase and in solution has been introduced. The combination of this formation pathway, based on the thermal decomposition of hydrobenzamide, with a state-of-the-art computational characterization of phenylmethanimine laid the foundation for its first laboratory observation by means of rotational electric resonance spectroscopy. Both E and Z isomers have been accurately characterized, thus providing a reliable basis to guide future astronomical observations. A further characterization has been carried out by nuclear magnetic resonance spectroscopy, showing the feasibility of this synthetic approach in solution. The temperature dependence as well as possible mechanisms of the thermolysis process have been examined.     

2-Methyltetrahydrofuran (2-MeTHF) as a versatile green solvent for the synthesis of amphiphilic copolymers via ROP,FRP, and RAFT tandem polymerizations

2-methyltetrahydrofuran (2-MeTHF) is a readily available, inexpensive, neoteric, bio-based solvent. It has been adopted across a wide range of chemical processes including the batch manufacture of fine chemicals, enzymatic polycondensations and ring opening polymerizations. To reduce the environmental burden related to the synthesis of pharmaceutical-grade polymers based on lactide and caprolactone, we envisaged the use of 2-MeTHF. For the first time, we combined a series of metal-free and enzymatic ROPs with free radical and controlled RAFT polymerizations (carried out separately and in tandem) in 2-MeTHF, in order to easily tune the chemistry and the architecture of the final polymers. After a simple purification, the amphiphilic polymers were formulated into nanoparticles and tested for their cytocompatibility in three model cell lines, to assess their application as potential polymeric excipients for nanomedicines.     

Reversible Activation of Water by an Air- and Moisture-Stable Frustrated Rhodium Nitrogen Lewis Pair

[Cp*Rh(κ³N,N′,P- L )][SbF₆] (Cp*=C₅Me₅), bearing a guanidine-derived phosphano ligand L , behaves as a “dormant” frustrated Lewis pair and activates H₂ and H₂O in a reversible manner. When D₂O is employed, a facile H/D exchange at the Cp* ring takes place through sequential C(sp³)−H bond activation.     

Multiplicity and Concentration Results for a Fractional Choquard Equation via Penalization Method

Potential Analysis - This paper is devoted to the study of the following fractional Choquard equation $$\varepsilon^{2s}(-{\Delta})^{s} u + V(x)u = \varepsilon^{\mu-N}\left(...     

Stabilization of the Triphosphallyl Ligand η3‐P3{P(O)H} at Iridium via Alkaline Activation of P4

The selective functionalization of the polyphosphorus moiety Ph₂PCH₂PPh₂PPPP present as a tetrahapto‐ligand in complex [Ir(dppm)(Ph₂PCH₂PPh₂PPPP)]⁺ ( 1 , dppm=Ph₂PCH₂PPh₂) was obtained by reaction of 1 with water under basic conditions at room temperature. The formation of the new triphosphaallyl moiety η³‐P₃{P(O)H} was determined in solution by NMR spectroscopy, and confirmed in the solid state by a single‐crystal X‐ray structure of the stable product [Ir(κ²‐dppm)(κ¹‐dppm)(η³‐P₃{P(O)H})] ( 2 ). In solution, 2 has a fluxional behavior attributable to the four P atoms belonging to the tetraphosphorus moiety in 1 and exhibits a chemical exchange process involving the two PPh₂ moieties of the same bidentate ligand, as determined by 1D and 2D NMR spectroscopy experiments carried out at variable temperature. The mechanism of the reaction was investigated at the DFT level, which suggested a selective attack of an in‐situ generated OH^? anion on one of the non‐coordinated phosphorus atoms of the P₄ moiety. The reaction then evolves through an acid‐assisted tautomerization, which leads to the final compound 2 . Bonding analysis pointed out that the new unsubstituted P₃‐unit in the η³‐P₃{P(O)H} moiety behaves as a triphosphallyl ligand.