Methyl tertbutyl ether

In collaboration with Haley Aldrich, Inc., HVEA tested the high-energy electron beam technology s ability to treat methyl tertbutyl ether (MTBE). The technology, known as electron beam (or E-beam) for this application, has treated MTBE in waste streams to concentrations below U.S. ERA maximum coutaminant levels. This level of treatmeut cau be attained at a cost of 1.00 to 1.25 per 1000 gal of water treated (D22179E, p. 1). 

It is also possible to determine the level of metabolites in urine. Urinary 2-thiothiazolidine-4-carboxylic acid is the best available indicator to assess the degree of occupational exposure to carbon disulfide (ACGIH 1994 Theinpont et al. 1990). Theinpont et al. (1990) described the isolation of this compound from urine prior to reverse phase high-performance liquid chromatography. It is based on liquid-liquid extraction with methyl tertbutyl ether, followed by affinity chromatography on organomercurial agarose gel. The detection limit of the procedure was 50 g of carbon disulfide/L of urine (Theinpont et al. 1990). 

Linnemann, V., Transport of volatile hydrocarbons through an undisturbed soil core into the atmosphere after contamination of the groundwater with the fuel additive methyl-tertbutyl ether (MTBE). Ph.D. thesis, 2002, University of Bonn, Germany. 

Figure 5.34 Infusion chromatograms covering the LC/MS assay time (2.5 minutes), obtained using the post-column infusion method shown in Figure 5.33, comparing the ability of different sample preparation methods to remove endogenous sample matrix components that interfere with the ionization of phenacetin. Panels (a) - (f) show the variation with time of the MS signed specific for the infused standard (phenacitin) following on-column injection of 10 p,L of a blank plasma sample prepared by one of the tested sample preparation methods, (a) Protein precipitation, (b) Oasis SPE. (c) Methyl-tertbutyl ether (MTBE) hquid-liquid extraction, (d) Empore C2 disk SPE. (e) Empore C8 disk SPE. (f) Empore Cl 8 disk SPE. Reproduced from Bonfigho, Rapid Commun. Mass Spectrom. 13,1175 (1999), with permission of John Wiley Sons, Ltd.

Methyl tertbutyl ether Propane, 2-methoxy 2-methyl- 16.34-04-4... 

SPMD extracts were cleaned up on a multilayer column filled with phosphoric acid/silica gel, potassium silicate, and silica gel using 4% methyl tert-butyl ether in hexane as eluent. A second purification was carried out on Florisil using methyl tertbutyl ether hexane (75 25) mixture as eluent. PCBs were isolated with a fined fractionation on a silica gel column by elution with hexane. 

Methyl tertbutyl ether (MTBE), 24,25 Methylxanthines, 955 Microbiological detection metiiods, 218 MiciochamberRPC (M-RPC), 325-326 Microchemical detection methods, 211-218 postchromatographic derivatization in situ, 212-218... 

Hydrolysis of racemic epoxide 18 was carried out using cells of R. glutinis. The cells (150 g) were suspended in 500 ml of 100 mM phosphate buffer pH 8.0 in a jacketed three-necked flask fitted with an air driven stirrer, condenser and stopper. A solution of 2.5 g racemic epoxide 18, in 50 ml of methyl tertbutyl ether was added to the stirred cell suspension. After 5.5 h at 28°C, the reaction was stopped. NaCI (180 g) was added and the mixture was extracted twice with an equal volume of ethyl acetate. The combined ethyl acetate layers were dried over anhydrous Na SO, filtered and the solvent was removed by a rotary evaporator to provide (S)-epoxide 18a in 48% solution yield. A portion (2.2 g) of the reaction product was dissolved in a mixture of heptanerethyl acetate (1 1) and repeatedly extracted with 0.10 M solution of Na B Oj in water. The organic layer provided 0.95 g of (S)-epoxide 18a with ee of >99% while the aqueous layer provided 1.02 g of (R)-diol 20 with ee of 79% [59]. 

To a solution of 5-bromo-l-(4-fluorophenyl)-l-(3-dimethylaminopropyl)-1,3-dihydroisobenzofuran (9 g, 0.024 mole) in tertbutyl methyl ether (150 mL) was added n-BuLi (1.6 M in hexanes, 40 mL) at -78 to -65°C. The temperature of the solution was allowed to raise to -30°C over a period of 2 hours. The reaction mixture was added to dry solid C02 (50 g). After addition, the mixture was left at room temperature for 16 hours. The volatile materials were removed in vacuo and the residue was taken up in water (100 mL). pH was adjusted to 5.5 by adding HCI (aqueous, 4 N). The aqueous phase was extracted with toluene (100 mL). The toluene was removed in vacuo and the 5-carboxy-l-(4-fluorophenyl)-l-(3-dimethylaminopropyl)-l,3-dihydroisobenzofuran was obtained as an oil. Yield 7.5 g. 

Higher carboxylic acids Tertbutyl methyl ether — Flame ionisation Carboxylic acids derivitivised with diazomethane 5 fig L-1 [628]... 

Plasma is spiked with S-(+)-naproxen in methanol-IS, extracted with tertbutyl methyl ether... 

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