Sodium 2-ethylhexanoate Research Articles

HNBR-based composite for seals used in coolant fluids: Swelling related to different silicates at high temperature

The effects of five fillers (two synthetic calcium silicates, one natural calcium silicate, talcum and a low specific surface area carbon black) filled with hydrogenated acrylonitrile butadiene rubber (HNBR) for possible use in seal for coolant fluids were developed by hardness, mechanical properties and hot air aging properties. Fluid blends were used to simulate the degraded OAT coolant. The swelling mechanism of HNBR vulcanizates was investigated by XRD, SEM, EDS, FT-IR and GC-MS. The results indicated that the filler with high specific surface area was easier to combine with HNBR. Hot air aging tests revealed a relatively high heat resistance and can meet the practical requirements. 2-ethylhexanoic acid hydrolyzed by sodium 2-ethylhexanoate as corrosion inhibitor react with silicate fillers in rubber to form 2-ethylhexanoate into the coolant, thus the network structure of rubber destroyed, while 2-ethylhexanoic acid and ethylene glycol diethyl-hexanoate as well as a small amount of ethylene glycol and water immersed into rubber. Higher crystallinity and lower specific surface area made natural CaSiO3 an efficient intrinsic base reserve to scavenge acidic products and effectively reduce the swell of filled HNBR.

Synthesis of bengamide E analogues and their cytotoxic activity

A series of bengamide E analogues were prepared from the corresponding polyketide chain and amino acids via amide coupling reactions. Opening of the polyketide chain lactone ring with α-aminolactams was successfully achieved under microwave irradiation in the presence of sodium 2-ethyl hexanoate. A cytotoxic activity evaluation against a panel of cancer cell lines (KB, HepG-2, Lu-1, MCF-7, HL-60 and Hela) indicated that the 2′R analogues were generally more cytotoxic than the 2′S analogues. Additionally, several analogues exhibited selective inhibition against various cancer cell lines: compounds 32a and 32b selectively inhibited MCF-7 cells, while 33b and 35b were more sensitive toward Lu-1 and HepG-2, respectively. Notably, some of the synthetic analogues possess cytotoxic activities with IC50 values less than 1µM.

Mechanochemical synthesis of chromium tris(2-ethylhexanoate) and evaluation of its catalytic activity in the reaction of ethylene trimerization

A method was developed for synthesis of chromium(III) tris(2-ethylhexanoate) by the mechanochemical interaction of chromium(III) chloride with sodium 2-ethylhexanoate without a solvent, followed by heating of the reaction mixture. The influence exerted by the conditions of the mechanical activation and the subsequent thermal treatment on the course of the processes and some properties of activated mixtures was studied. Chromium(III) tris(2-ethylhexanoate) can be isolated from the reaction mixture in a ∼75% yield. Both the activated reaction mixture and the target product obtained exhibit a high catalytic activity and selectivity in the reaction of ethylene trimerization.

Catalytic Desulfurization of Dibenzothiophene with Palladium Nanoparticles

The thermal reduction of [(PEt3)2PdMe2] (1 mol%), which was produced in situ from [(PEt3)2PdCl2] (1) and 2 equiv of MeMgBr in toluene solvent, yielded palladium nanoparticles that in conjunction with MeMgBr effected the desulfurization of dibenzothiophene (DBT). The reaction resulted in the generation of the sulfur-free compound 2,2'-dimethylbiphenyl, in high yields (60%). The use of several stabilizing agents such as sodium 2-ethylhexanoate and hexadecylamine was also addressed herein, their use resulting in a significant improvement of the desulfurization reaction that reached up to 90% conversion of DBT into the mentioned biphenyl. The palladium nanoparticles formed during the reaction were characterized by transmission electron microscopy and exhibited a smaller size and a lesser extent of agglomeration whenever stabilizers were used.

Repeated use of the in-situ modified nickel catalyst for the enantio-differentiating hydrogenation of 2-octanone

Repeated use of the in-situ modified reduced nickel catalyst prepared from nickel oxide was carried out for the enantio-differentiating hydrogenation of 2-octanone. The tartaric acid (TA)–NaBr in-situ modified reduced Ni retained over 60% of the enantio-differentiating ability (eda) of the catalyst in the hydrogenation at 373 K for repeated 16 runs by the addition of tartaric acid and sodium 2-ethylhexanoate to the reaction media before every other run. The quantitative analyses of the adsorbed species on the catalyst surface revealed that the tartaric acid and sodium ions adsorbed in the 1st run were gradually desorbed during the repeated runs. The result supports the necessity of the addition of tartaric acid and sodium 2-ethylhexanoate to the reaction media every other run for retaining the enantio-differentiating ability.

An Expedient Synthesis of LAF389, a Bengamide B Analogue

An optimized, convergent, safe synthesis of LAF389 (9), an anti-cancer agent analogous to bengamide B, is described. Starting from α-d-glucoheptonic (d-glycero-d-gulo-heptonic acid) γ-lactone (10), the lactone 15 was constructed in five steps. Major improvements were made in the preparation of the aldehyde precursor 14 and subsequent olefination to yield 15 via a modified Julia protocol. This olefination was significantly improved by using TMSCl as an additive. The second fragment of the drug substance, ε-caprolactam 7, was obtained in two one-pot operations from (5R)-5-hydroxy-l-lysine (1). Finally, opening 15 with 7 using sodium 2-ethyl hexanoate (Na-EH) gave 8, which on deprotection yielded LAF389.

Total synthesis of bengamide E

A total synthesis of bengamide E is reported. The synthesis includes the utilization of d-tartrate as the chiral building block, construction of the E-olefin by the Julia protocol, an anti-aldol reaction to generate C-2 and C-3 stereocenters, and coupling of the thioester with caprolactam hydrochloride using sodium 2-ethylhexanoate.

Highly Durable Enantio-Differentiating Nickel Catalyst for Repeated Use for the Hydrogenation of Methyl Acetoacetate

Abstract The enantio-differentiating hydrogenation of methyl acetoacetate was repeated 30 times over a fine Ni powder catalyst while modifiers (optically active tartaric acid and NaBr) were directly added to the reaction media only in the first run. Over 80% optical yields were attained for the repeated runs. The addition of sodium 2-ethylhexanoate increased the optical yields in the subsequent runs. The very simple and highly durable enantio-differentiating nickel catalyst for repeated use was developed by an in situ modification.

A mild method for ring-opening aminolysis of lactones

A mild and general method for lactone aminolysis is reported. Sodium 2-ethylhexanoate (NaEH) is found to serve both as a base and a catalyst in aminolysis of a variety of lactones by benzylamine hydrochloride. The nearly neutral pH conditions make this method applicable to many acid/base sensitive substrates.

Differential sensitivity of the SWV and C57BL/6 mouse strains to the teratogenic action of single administrations of cadmium given throughout the period of anterior neuropore closure.

When administered to mice during gestation, the heavy metal, cadmium, is known to induce malformations of the neural tube, craniofacial region, limbs, trunk, viscera, and axial skeleton that vary in scope and severity among inbred strains of mice. Two strains, C57BL/6 and SWV, were previously shown to differ in their susceptibility to exencephaly induced by many teratogenic treatments, including sodium 2-ethylhexanoate, hyperthermia, valproic acid, and carbon dioxide, with the SWV strain being consistently more sensitive than the C57BL/6 strain. These findings support the observation of Finnell et al. ([1988] Teratology 38:313-320) of shared hierarchies of relative susceptibility to exencephaly induced by biochemically distinct teratogens, and suggest that the SWV strain would also be more sensitive to exencephaly induced by cadmium. In the present study, pregnant mice from the two strains were exposed to single i.p. injections of cadmium chloride at 4 mg/kg-BW on day 6.5, 7.0, 7.5, 8.0, 8.5, or 9.0 of gestation. Fetuses were removed by cesarean section on day 18 of gestation and scored for malformations. The C57BL/6 strain was observed to be more sensitive than the SWV strain to the induction of exencephaly by cadmium on days 6.5, 7.0, and 8.0, with mean litter percentages of 3.6%, 88.3%, and 62.2%, respectively, compared to 0.0%, 4.1%, and 27.7% for the SWV strain. This finding provides evidence in contrast to the hypothesis of shared hierarchies of sensitivity to teratogen-induced exencephaly. Data on a number of other cadmium-induced malformations are also presented.

Sodium 2-ethylhexanoate: A mild acid scavenger useful in acylation of amines

A highly useful method for the acylation of amines with acid chlorides utilizing sodium 2-ethylhexanoate as the base is described. This procedure is superior to the Schotten-Baumann conditions whenever the product is water soluble.

Murine teratology and pharmacokinetics of the enantiomers of sodium 2-ethylhexanoate

A mouse model for the induction of exencephaly with sodium (±)-2-ethylhexanoate has been developed using multiple administration regimes. With three consecutive administrations at one-half-day intervals, the most sensitive time to induce exencephaly was Gestational Days 8–9. Using the racemic substance it was determined that the SWV strain was more sensitive to the induction of exencephaly than the C57BL 6NCrlBR strain. The enantiomers of 2-ethylhexanoic acid were separated via preparative HPLC to greater than 99.8% optical purity, and greater than 99% purity according to a gas chromatographic analysis. It was demonstrated that the ( R)-enantiomer is a more potent teratogen than the ( S)-enantiomer for the induction of exencephaly as well as malformations of other organ systems. Pharmacokinetic analyses for each of the enantiomers were performed in maternal plasma, maternal muscle, and embryo. The pharmacokinetics showed that the peak concentration ( C max) for both enantiomers in the three compartments was approximately equivalent and was attained within 15 min following the third administration. The area under the concentration versus time curve values for the two enantiomers were approximately 10% higher for the ( R)-antipode because of a slightly slower elimination of this compound. There was negligible (or no) racemization of the two enantiomers in the biological samples. The results suggest that teratologic differences in the enantiomers of sodium 2-ethylhexanoate are not due to differences in the concentrations of these antipodes in the embryo, but more likely result from the specific interaction of the enantiomers with chiral molecules in the embryo.