Of 2-methoxyethanol

Etacelasil. 2-Chloroethyl-tris (2-methoxy-ethoxy)-silane [37894 6-5] (Etacelasd, Alsol) (27) is made by the reaction of three moles of 2-methoxyethanol with one mole of Cl2SiCH2Cl. The name Alsol should not be confused with aluminum acetotartrate, also known as Alsol. Etacelasil is... 

A calibration curve for the range 0.2-10 mg fluoride ion per 100 mL is constructed as follows. Add the appropriate amount of standard sodium fluoride solution, 25 mL of 2-methoxyethanol, and 10 mg of a buffer [0.1 Af in both sodium acetate and acetic (ethanoic) acid] to a 100 mL graduated flask. Dilute to volume with distilled water and add about 0.05 g of thorium chloranilate. Shake the flask intermittently for 30 minutes (the reaction in the presence of 2-methoxyethanol is about 90 per cent complete after 30 minutes and almost complete after 1 hour) and filter about 10 mL of the solution through a dry Whatman No. 42 filter paper. Measure the absorbance of the filtrate in a 1 cm cell at 540 nm (yellow-green filter) against a blank, prepared in the same manner, using a suitable spectrophotometer. Prepare a calibration curve for the concentration range 0.0-0.2 mg fluoride ion per 100 mL in the same way, but add only 10.0 mL of 2-methoxyethanol measure the absorbance of the filtrate in a 1 cm silica cell at 330 nm. 

Very pure docosanedioic acid can be obtained by another recrystallization from about 450 ml. of 2-methoxyethanol. The recrystallized acid is collected on a Buchner funnel, and the well-pressed filter cake is suspended in 200 ml. of 95% ethanol, refiltered, and dried in air weight 112 g. (61%) m.p. 126-127° neutralization equivalent, 185-187. 

A 1/1,2/1 mixture of 2-methoxyethanol/polyacrylamide + hydrogen per-oxide/toluene respectively volatilised slowly and intermittently by heating over a period of four weeks. The detonation was explained by the ether-alcohol oxidation by the peroxide. 

Rao et al. [46] reported the use of a spectrophotometric method for the determination of primaquine phosphate with ninhydrin. Standard solution of 0.01% primaquine phosphate solution (3 mL) or solution prepared from the drug or its tablets was mixed with 2 mL of water, 5 mL of 2-methoxyethanol and then with 4 mL of ninhydrin reagent. The mixture was boiled for 35 min, and, after cooling and dilution to 25 mL with water, the absorbance was measured at 570 nm versus a reagent blank. Beer s law was obeyed from 4 to 20 pg/mL with recoveries of 99.4— 100.2% for 25 mg of primaquine phosphate. 

Smialowicz, R.J. et al., Differences between rats and mice in the immunosuppressive activity of 2-methoxyethanol and 2-methoxyacetic acid, Toxicology, 74, 57, 1992. 

Scott WJ, Fradkin R, Wittfoht W, et al Teratologic potential of 2-methoxyethanol and transplacental distribution of its metabolite, 2-methoxyacetic acid, in non-human primates. Teratology 39 363-373, 1989... 

Feuston MH, Kerstetter SL, Wilon PD Teratogenicity of 2-methoxyethanol applied as a single dermal dose to rats. Fundam Appl Toxicol 15 448M-56, 1990... 

Smialowicz RJ, Riddle MM, Luebke RW, et al Immunotoxicity of 2-methoxyethanol following oral administration in Fischer 344 rats. Toxicol Appl Pharmacol 109 494—506, 1991... 

Williams WC, Riddle MM, Copeland CB, et al Immunological effects of 2-methoxyethanol administered dermally or orally to Fischer 344 rats. Toxicology 98(1-3) 215-223, 1995... 

Methoxyethyl acetate is hydrolyzed in vivo to form 2-methoxyethanol, which is subsequently metabolized to 2-methoxyacetic acid, a proported teratogenic substance. Consequently, the acetate is expected to show profiles of developmental and reproductive toxicity similar to those of 2-methoxyethanol (qv). In a case report, a woman who was extensively exposed to 2-methoxyethyl acetate, both dermally and probably by inhalation during pregnancy, gave birth to two sons with hypospadias. Because family history and medical examination showed no overt risks other than the significant exposure of the mother, and because 2-methoxyethyl acetate can cause teratogenic effects in animals, the malformations were attributed to the exposure. 

Oxidation of 2-methoxyethanol or 1,2-ethanediol by [0s04], in the presence of a porphyrin, is used to prepare [Osn(P)(CO)(X)] complexes [P is a porphyrinato(2-) ligand] (139). Recently, more convenient preparations of porphyrinato complexes were developed using the reactions of LOs3(CO)i2] with the appropriate porphyrin (Section II,C,4,d) (38, 40, 140,141). Electrochemical studies show that both the Os(III) and Os(III)/porphyrin-cation-radical complexes are moderately stable... 

Ru3(CO)12 in benzene [33], in toluene [34], in acetic or propionic acid [31], or in decalin [35], or RuC13 in DEGE [36-38] or glycol and formaldehyde [39] have also been used. Tsutsui s protocol using Ru3(CO)12 [33] was frequently mentioned [40-43]. Boiling for 22 to 60 h was necessary in most cases. Only the use of 2-methoxyethanol [44] or decalin [35] as a solvent appears to have been a notable improvement because a reduction of the reaction time to 4 to 5 h in some cases was achieved. 

The pKa values of perhydropyridof 1,2-a]pyrazin-l -one, its 2-methyl derivative and their N-5 oxides were determined by potentiometric titration in a 4 1 mixture of 2-methoxyethanol and H20 (81BAP423).The partition coefficients of 3-substituted 2,3,4,4a,5,6-hexahydro-l//-pyrazino[l,2-a]-quinolines have been determined in water-l-octanol [80IJC(B)879],... 

Approximately lOmg of the lignin (Note 1), accurately weighed to the nearest 0.01 mg, is placed in a 100-ml volumetric flask containing approximately 80 ml of a mixture of 2-methoxyethanol-ethanol (2 3, v/v). When the sample is completely dissolved, the solution is diluted to 100 ml with the 2-methoxyethanol-ethanol mixture. This sample solution is the stock solution. 

Pharmacokinetic information that relates blood concentration to toxic response is critical in defining such dose-response relationships, but information on peak blood concentrations or blood concentrations over time (area under the curve (AUC)) is seldom available. One agent for which such information has been published is 2-methoxyacetic acid (2-MAA), the active metabolite of 2-methoxyethanol. Terry et al. (1994) showed that peak concentration was related to neural tube defects observed after exposure in mice on gestation day 8, whereas area under the curve was shown to be related to limb defects after exposure to 2-MAA on gestation day 11 (Clarke et al. 1992), suggesting that the time of exposure and pattern of development of the susceptible organ... 

Decarbonylation of 2-methoxyethanol provides the CO ligands for formation of the five-coordinate bulky phosphine complexes [RuHCl(CO)L2] (L = PCy,2472 PBu 2R (R = Me, Et)1712]. These compounds readily take up CO to give [RuHCl(CO)2L2] (L = PCy3,1813 PBu 2R1712) with trans L and... 

In a number of groundbreaking explorations,46 Wudl, Hummelen, and coworkers showed that photoinduced [2 + 2] cycloaddition of singlet oxygen to one of the electron-rich enamine-type double bonds of azahomo [60] fullerene derivative 53 (Scheme 1.8), followed by decomposition of the 1,2-dioxetane intermediate (not shown), led to ketolactam ( )-54, the first cluster-opened fullerene with a free orifice.153 Under synthetic conditions mimicking events observed in the gas phase,154 acid-induced loss of 2-methoxyethanol from... 

The flame decompositions of 2-hydroxyethyl nitrate, 2-methoxyethyl nitrate and 2-ethoxyethyl nitrate have been studied using a flat flame burner [135]. The major products of very rapid reaction in the flame front are nitric oxide, carbon monoxide, water, formaldehyde, methyl formate, methanol and a large amount of unidentified material. The absence of 2-methoxyethanol and of nitrogen dioxide, and presence of only minor amounts of dimethyl ether is of some importance. 

All mass spectrometric analyses were carried out on a triple quadrupole mass spectrometer (TSQ-700) from Finnigan-MAT (San Jose, CA) equipp with an electrospray ion source (ESI) operating at atmospheric pressure. Mass spectra were recorded in the positive ion mode. The electrospray needle was operated at a differential of 3-4 kV, the conversion dynode was set to -15 V. The drying gas was nitrogen and the temperature was set to about 200 °C. A sheath flow of 2-methoxyethanol was delivered with 2 pJ/min and the nitrogen sheath gas was set at 50 psi. Samples were directly introduced into the source with a flow rate of 2 p.l/min. Scans were continuously taken every three seconds. 

Caution. As hydrogen is liberated before hydrogenation starts when 2-methoxyethanol reacts with sodium and aluminium, the volume of the reaction mixture must not exceed 55% of the total free volume of the autoclave and the maximum pressure of hydrogen must not exceed the permitted working pressure. This part of the preparation is exothermic and the temperature of the reaction mixture must not exceed 170°. When more than 15 moles of sodium dihydridobis(2-methoxyethoxo)aluminate(l-), is prepared it is necessary to control this reaction by slow addition of 2-methoxyethanol to sodium and aluminum in the closed autoclave. 

Considerably improved filtration may be accomplished when the fritted-glass filter is covered with a 1-1.5 cm layer of powdered aluminum (or dried Celite filter aid). Before starting the filtration, the whole apparatus is evacuated. Then the reaction mixture is poured into the fritted-glass filter while nitrogen is introduced slowly into the space above the filter. The solids are washed with 15 ml of benzene and the filtrates are combined to give 262 g of clear yellowish solution. The yield with respect to the initial amount of 2-methoxyethanol is 98.1%. Anal. Calcd. for Na[AlH2(0CH2CH20CH3)2] Na, 11.37 Al, 13.35 H, 0.997%. Found Na, 6.04 Al, 6.94 H, 0.537%, Na Al H = 1.02 1 2.07. 

Ghosh SK, Hazra DK. Solvent effects on the dissociation of benzoic acid in aqueous mixtures of 2-methoxyethanol and 1,2-dimethoxyethane at 25°C. ] Chem Soc Perkin Trans 1989 2 1021-1024. 

It has been shown that one of the major processes is the scission of an 0-H bond. The resulting radical is unstable and largely fragments into formaldehyde and a hydroxymethyl radical (Scheme 5). The same reaction has been proposed to account for some products in the photolysis of 2-methoxyethanol (159). The formation of molecular hydrogen together with glycolaldehyde, as well as the fragmentation into formaldehyde and methanol (Scheme 5) were postulated as molecular processes in order to account for the products and their quantum yields. 

Nelson BK, Snyder DL, Shaw PB. Developmental toxicity interactions of methanol and radiofrequency radiation of 2-methoxyethanol in rats. Int J Toxicol2001 20(2) 89-100. 

Hyperthermia induced by an elevation in ambient temperature following RF radiation is known to be associated with fetal developmental effects. 2-Methoxyethanol is a known teratogen. In a study on laboratory animals it was demonstrated that combined exposure to RF and 2-methoxyethanol enhanced the adverse effects produced by either agent alone. It was also noted that teratogenic effects of 2-methoxyethanol were observed at levels below those found for the solvent alone, when it was co-administered with RFJ251... 

Aluminium, gallium and indium can be retained on the anion exchanger from a solution of 2-methoxyethanol and 6 M HCl, and can then be sequentially eluted with 1 M HCl [13]. 

A 2-methoxyethanol solution (60 mL) of triphenylphosphine (1.6 g, 6.0 mmol) is stirred vigorously and refluxed. Hydrated ruthenium trichloride (0,26 g, 1.0 mmol) dissolved in a mixture of 2-methoxyethanol (20 mL) and aqueous formaldehyde (20 mL, 40 w/v %) is rapidly added. The reaction mixture is refluxed for 10 min and then is allowed to cool to room temperature. The resulting cream-white microcrystals are filtered off and washed with ethanol (2x10 mL), water (2x10 mL), ethanol (2 x 10 mL), and finally with hexane (10 mL) and then dried under vacuum. Yield 0.89 g (93 %). 

Moslen MT, Kaphalia L, Balasubramanian H, et al. 1995. Species differences in testicular and hepatic biotransformation of 2-methoxyethanol. Toxicology 96 217-224. 

The very large solvent effect observed in these reactions (rates of the order of 10 times faster in dichloroethane than in 2-methoxyethanol ) has been interpreted in terms of solvation effects, which in the case of 2-methoxyethanol can prevent the binding of the substrate to a considerable extent. This would not be the case for the much more poorly coordinating 1,2-dichloroethane, once again pointing to the importance of vacant or readily available coordination sites for efficient catalysis to occur. 

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