A series of lithium, sodium, and potassium complexes with phenoxo-imine ligands M[(O-2-(RNCH)C6H4] [R = C6H5; 2- t BuC6H5; 2,6- i Pr2C6H3] and [O-2-(RNCH)-4,6- t Bu2C6H4] [R = C6H5; 2- t BuC6H5; 2,6- i Pr2C6H3] 1–3(a–f) have been synthesized. The molecular structures in the solid state of some of these complexes have been determined by X-ray diffraction. These compounds show different nuclearities and geometries around the metal center depending on the nature and the pocket of the ligand substituents. Of particular interest is the structure of compound 3e, being the first example of a potassium cubane complex obtained with this kind of ligand. The structural behavior in solution has also been studied by diffusion-ordered NMR spectroscopy (DOSY), showing a direct correlation between aggregation behavior and polymerization activity. Compounds 1–3(a–f) are extremely active catalysts in the ring-opening polymerization (ROP) of rac-lactide, achieving conversions of 100% in less than 1 min and heterorich-PLA that is modified by the metal atom and the ligand substituents. BnOH was used as co-initiator, and the presence of large amounts of the alcohol produces the immortal polymerization of rac-lactide in a more controlled process. Stoichiometric reactions involving the catalysts, BnOH, and lactide demonstrated an activated monomer mechanism for the polymerization of rac-lactide.

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A Zn-based metal-organic framework (MOF) with hydrazinebenzoate linkers was evaluated as antimicrobial material against the Gram-positive bacterium Staphylococcus aureus. The material inhibits bacterial growth and metabolic activity, with a half maximal effective concentration of about 20 mg L -1 [a

Crystal size 0.35 x 0.20 x 0.19 mm Theta range for data collection 3.33 to 27.51 deg. Limiting indices -18<=h<=18, -12<=k<=12, -14<=l<=14 Reflections collected / unique 34587 / 3713 [R(int) = 0.0509] Completeness to theta = 27.51 99.6 % Absorption correction Semi-empirical from equivalents Max. and min. transmission 0.785 and 0.597 Refinement method Full-matrix least-squares on F^2

Reduction of phenol-imine derivatives RЈN=CH(3,5-R 2 C 6 H 2 -2-OH) (R = tBu; RЈ = C 6 H 5 1a, p-MeC 6 H 4 1b, Cy 1c, tBu 1d, 2,6-Me 2 C 6 H 3 1e; R = H; RЈ = p-MeC 6 H 4 1f; Cy = cyclohexyl) with MBH 4 (M = Li, Na) or AlLiH 4 in ethyl ether or thf at room temperature affords the phenol-amine compounds RЈNHCH 2 (3,5-R 2 C 6 H 2 -2-OH) 2a-c and 2e,f. The N-R- [2,4-ditert-butyl]benzo-1-oxa-3-azine species (R = tBu 2d1, 2,6-Me 2 C 6 H 3 2e1) are obtained by Mannich reaction of 2,4-ditert-butylphenol with RNH 2 in refluxing methanol. Intermediate 2d1 is converted in ethanol at room temperature into N-tert-butyl [2-hydroxy-3,5-di-tert-butyl]benzylamine (2d), whereas 2e is not obtained from 2e1 by using this procedure. N-alkyl,N-tert-butyl[2-hydroxy-3,5-di-tert-butyl]benzylamine compounds tBuN(R)CH

A variety of N-heterocyclic carbene (NHC) complexes of general formula fac-[Mn(NHC)(CO) 3 (bipy)] + have been prepared by reaction of the manganese(I) isocyanide complexes fac-[Mn(CNR)(CO) 3 (bipy)] + with propargylamines and propargylic alcohols and characterized by spectroscopic and X-ray diffraction methods.

Reaction of Ti{η 5 -C 5 H 4 SiMe 2 -η-N(CH 2 ) 2 NRR′}Cl 2 with Nb(η 5 -C 5 H 4 SiMe 2 Cl)Cl 4 affords the tethered heterodinuclear complexes TiCl 2 {η 5 -C 5 H 4 SiMe 2 -η-N(CH 2 ) 2 -κ-NRR′}Nb(η 5 -C 5 H 4 SiMe 2 -Cl)Cl 4 , which are thermally unstable in solution and evolve to render an equimolar mixture of Ti(η 5 -C 5 H 4 SiMe 2 Cl)Cl 3 and the corresponding cyclopentadienyl-amido niobium compounds, Nb{η 5 -C 5 H 4 SiMe 2 -η-N(CH 2 ) 2 NRR′}Cl 3 . These compounds are straightforwardly obtained from the reaction of Nb(η 5 -C 5 H 4 SiMe 2 Cl)Cl 4 with 1 equiv of the appropriate diamine, NH 2 (CH 2 ) n -NRR′, in the presence of 2 equiv of NEt 3 , in high yield. In this reaction, the presence of the functional pendant chain plays a central role not only in determining the course of the reaction but also in stabilizing the final product, from both an electronic and a steric point of view. The molecular structure of Nb{η 5 -C 5 H 4 SiMe 2 -η-N(CH 2 ) 3 -η-NH 2 }Cl 3 has been determined by X-ray diffraction methods.

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