The solvation structure around the Li + ion in a mixed cyclic/linear carbonate solution, an important factor for the performance of lithium-based rechargeable batteries, is examined by measuring and analyzing the noncoincidence effect observed for the CO stretching Raman band. This technique has the advantage of perceiving relative distances and orientations of solvent molecules clustering around an ion in the first solvation shell and, hence, of developing information on the solvation structure along the wavenumber axis rather than along the intensity axis of the spectra. It is shown that, taking the solution of Li + ClO 4 − in the 1:1 mixed solvent of propylene carbonate (PC) and diethyl carbonate (DEC) as an example case, the Li + ion is preferentially solvated by PC molecules [primarily as (PC) 3 (DEC) 1 Li + ] and is totally protected from direct interaction (contact ion pairing) with the ClO 4 − ion. The solvation structures in neat PC and neat DEC solvents are also discussed.I on solvation is a central, and still an open, issue in many chemical, biochemical, and electrochemical processes. One of those important processes would be the functioning of lithium-based rechargeable batteries. 1−3 Their performance depends on the electrode materials and processes on the one hand and on the charge carrier concentration and mobility in the electrolyte solution on the other hand. With regard to the latter, high charge density of the Li + ion should be sufficiently stabilized, and at the same time, the electrolyte solution should have sufficiently high fluidity. A usual practice to make these two factors compatible is to employ a mixed solvent, consisting of a highly dipolar liquid such as a cyclic carbonate stabilizing the high charge density (but highly viscous) and a liquid of lower viscosity such as a linear carbonate (being less dipolar). Quite often ethylene or propylene carbonate (with dielectric constant ε = 65−90 and viscosity η ≅ 2.5 cP, abbreviated as EC and PC) is used for the former, and dimethyl, diethyl, or ethyl methyl carbonate (with ε ≅ 3 and η = 0.6−0.9 cP, abbreviated as DMC, DEC, and EMC) is used for the latter.The solvation structure around the Li + ion, especially that of the first solvation shell, has been suggested to be important for the interphase chemistry on the electrodes. 4−6 The use of a mixed solvent introduces a complexity in this. One controversial subject in this regard is the presence/absence of the preferential solvation and (if present) its nature for the Li + ion in a mixed cyclic/linear carbonate solution. 7−19 On the basis of electrospray ionization mass spectroscopy (ESI-MS), 7,8 it has been suggested that there is a strong preferential solvation for Li + in EC/EMC, with the Li + (EC) 2 species as the main ingredient. 7 The same type of preferential solvation (i.e., with a higher population of cyclic carbonate around the ion than in the bulk) has also been suggested in some NMR studies 9−11 but with a much larger total solvation number (≥6). 9,20 It has been argued that some...

The azido transfer procedure of heteroaryllithium and tosyl azide was used to synthesize selected 2- and 5-azidoazoles. This procedure, which is based on the fragmentation of the appropriate lithium triazene salts 1a-7a, successfully afforded 2-azido-N-methylimidazole 1, 2-azido-1,3-thiazole 2, 2-azidobenzo-1,3-thiazole 3, 5-azido-N-methylpyrazole 4, 5-azido-N-methylimidazole 6[via 2-(trimethylsilyl)-5-azido-N-methylimidazole 5], and 5-azido-1,3-thiazole 7 (via 5-lithio-1,3-thiazole), but attempts to prepare 5-azido-2-(trimethylsilyl)-1,3-thiazole 8 from the corresponding triazene 7a failed, affording only the desilylated azide in poor yield. Azides - underwent 1,3-dipolar cycloaddition when mixed with neat (trimethylsilyl)acetylene, giving 1-heteroaryl-4-trimethylsilyl-1,2,3-triazoles 1b-7b generally in very high yields.

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Ruthenium complexes have proved to exhibit antineoplastic activity, related to the interaction of the metal ion with DNA. In this context, synthetic and theoretical studies on ruthenium binding modes of thymine acetate (THAc) have been focused to shed light on the structure-activity relationship. This report deals with the reaction between dihydride ruthenium mer-[Ru(H)2(CO)(PPh3)3], 1 and the thymine acetic acid (THAcOH) selected as model for nucleobase derivatives. The reaction in refluxing toluene between 1 and THAcOH excess, by H2 release affords the double coordinating species κ1-(O)THAc-, κ2-(O,O)THAc-[Ru(CO)(PPh3)2], 2. The X-ray crystal structure confirms a simultaneous monohapto, dihapto- THAc coordination in a reciprocal facial disposition. Stepwise additions of THAcOH allowed to intercept the monohapto mer-κ1(O)THAc-Ru(CO)H(PPh3)3] 3 and dihapto trans(P,P)-κ2(O,O)THAc-[Ru(CO)H(PPh3)2] 4 species. Nuclear magnetic resonance (NMR) studies, associated with DFT (Density Function Theory)-calculations energies and analogous reactions with acetic acid, supported the proposed reaction path. As evidenced by the crystal supramolecular hydrogen-binding packing and 1H NMR spectra, metal coordination seems to play a pivotal role in stabilizing the minor [(N=C(OH)] lactim tautomers, which may promote mismatching to DNA nucleobase pairs as a clue for its anticancer activity.

The roots of two cultivars of Paeonia, namely Paeonia officinalis “Rubra Plena” and Paeonia “Pink Hawaiian Coral”, have been extracted with chloroform. The composition of the lipid fraction, analyzed by GC–MS technique, revealed the absence of paeonol and the presence of phenol, benzoic acid, fatty acid—and some sterol—derivatives. The chloroformic extracts have been tested on normal and several cancer cell lines but showed antiproliferative activity only on the ovarian carcinoma and the osteosarcoma. The biological activity of extracts was investigated mainly by confocal microscopy, flow cytometry and quantum phase imaging. The results indicated that the root extracts induced a hyperpolarization of mitochondria and an increase in reactive oxygen species levels, without inducing cell death. These effects are associated to an increased doubling time and a retarded confluence.