Octyl ether

Both methyltriethylphosphonium fluoride and methyltributylphospho-nium fluoride have been prepared The latter generates benzyl fluoride from benzyl chloride in 80% yield and ethyl fluoroacetate from ethyl bromoacetate in 53% yield Methyltnbutylphosphonium fluoride converts 1-bromododecane to a 50 50 mixture of 1-fluorododecane and 1-dodecene Methyltnbutylphosphonium fluoride also quantitatively forms styrene from 1-bromo-1-phenylethane [26] Methyl-tnbutylphosphonium fluonde is the reagent of choice for the conversion of N,N dimethylchloroacetamide to its fluoride, but it is not able to convert chloro-acetonitnle to fluoroacetomtrile Methyltnbutylphosphonium fluoride changes chloromethyl octyl ether to the crude fluoromethyl ether in 66% yield The stereoselectivity of methyltnbutylphosphonium fluoride is illustrated by the reac tions of the 2-tert-butyl-3-chlorooxiranes [27] (Table 2)... 

FIG. 1 Kinetics of the hydrolysis of sodium hexyl sulfate and several alcohol ether sulfates. 1, Sodium hexyl ether (1 PrO) sulfate, K = 0.0075 min1 2, sodium octyl ether (1 PrO) sulfate, AT, - 0.0071 min 1 3, sodium octyl ether (1 EO) sulfate, AT, = 0.0051 min1 and 4, sodium hexyl sulfate, AT, = 0.0037 min1. 

Galland, A., Girault, H., Testa, B., Carrupt, P. A. Solvatochromic analysis of partition coefficients in the o-nitrophenyl octyl ether (o-NPOE)/water system. Helv. Chim. Acta 2003, 86, 3533-3547. 

Quinn et al. studied ET at micro-ITIES supported by micropipettes or microholes [16]. The studied systems involved ferri/ferrocyanide redox couple in aqueous phase and ferrocene, dimethylferrocene, or TCNQ in either DCE or o-nitrophenyl octyl ether. Sigmoidal, steady-state voltammograms were obtained for ET at the water-DCE interface supported at a micropipette. The semilogarithmic plot of E versus log[(/(j — /)//] was... 

FIG. 9 Differential capacity C of the interface between 0.1 M LiCl in water and 0.02 M tetrabu-tylammonium tetraphenylborate ( ) or tetrapentylammonium tetrakis[3,5-bis(trifluoromethyl)phe-nyl]borate ( ) in o-nitrophenyl octyl ether as a function of the interfacial potential difference (From Ref 73.)... 

This reaction is the reverse of the initial ketyl radical formation by the benzophenone triplet and is therm Q4ynamically favorable. The experiments using optically active alcohols as source of hydrogen atoms show, however, that under normal conditions this reaction is unimportant. This is probably due to other, more efficient pathways for reaction of the ketyl radicals or perhaps to diffusion rates which separate the radicals before reverse transfer can occur. That this reaction can be important in some cases even without the presence of sulfur compounds was shown by studying the photoreduction of benzophenone in optically active ethers.<68) Although the reaction of benzophenone in methyl 2-octyl ether is only 0.17 times as fast as that in isopropanol, ethers can be used as sources of hydrogen atoms for photoreduction ... 

Using optically active methyl 2-octyl ether, an appreciable racemization of the unreacted ether isolated was observed, in contrast to the result using an alcohol, indicating that about half of the initially produced radicals underwent reverse transfer. The presence of mercaptan or disulfide greatly increased the amount of racemization ... 

Write line formulas for (a) dibutyl ether, (b) propyl phenyl ether, and (c) methyl octyl ether. 

Dioctyl sebacate (DOS) with relative permittivity e of 3.9 and 2-nitrophenyl octyl ether (NPOE) with e = 23.9 are the traditionally used sensor membrane plasticizers. The choice of a plasticizer always depends on a sensor application. Thus, NPOE appears to be more beneficial for divalent ions due to its higher polarity, but for some cases its lipophilicity is insufficient. Furthermore, measurements with NPOE-plasticized sensors in undiluted blood are complicated by precipitation of charged species (mainly proteins) on the sensor surface, which leads to significant potential drifts. Although calcium selectivity against sodium and potassium for NPOE-based membranes is better by two orders of magnitude compared to DOS membranes, the latter are recommended for blood measurements as their lower polarity prevents protein deposition [92],... 

The reduction of aldehydes with the combination Et3SiH/BF3 OEt2 gives both the alcohol and the symmetrical ether,70 as do the Et3SiH/TFA (and other acids) combinations.313 Addition of boron trifluoride etherate to a mixture of 1-octanal and triethylsilane leads to the formation of di-n-octyl ether in 66% yield and //-octyl alcohol in 34% yield (Eq. 155).74... 

Octyl bromide, b385 Octyl chloride, c204 Octyl cyanide, n95 Octyldimethylamine, d649 Octyl ether, d729 Octyl iodide, i44 Octyl sulfide, d730 Oleic acid, oil... 

Fig. 18a. 11. Chemical structures of commonly used plasticizers in membranes of ion-selective electrodes. DOS, dioctyl sebacate NPOE, nitrophenyl octyl ether.

A detailed study of the formation of n-octyl ethers under solidrliquid two-phase conditions in the absence of an added solvent has been reported [10], Potassium alkoxides tend to produce higher yields of the ethers than do the corresponding sodium derivatives, but octene is the major product in the reaction of 1-bromooctane with potassium t-butoxide. High temperatures also tend to promote the preferential formation of octene and slightly higher yields of the ethers are obtained using n-octyl tosylate in preference to n-octyl bromide. p-Fluorinated acetals have been prepared either under basic catalytic liquidrliquid or solidrliquid conditions from the fluori-nated alcohol and dichloromethane [11] with displacement of the fluorine atoms. 

Method E The alcohol (25 mmol), powdered KOH or NaOH (25 mmol), and Aliquat (0.2 g, 0.5 mmol) are stirred for 10 min and n-C H,7Br (1.93 g, 10 mmol) is then added. The reaction mixture is worked up to yield the alkyl octyl ether as described in 3.I.I.D. Method F. Under microwave irradiation The alcohol (10 mmol), haloalkane (25 mmol),... 

Ishibashi et al. devised a potentiometric sensor for the determination of non-ionic surfactants which they improved in several steps. Initially, the authors used a sensor based on a PVC membrane plasticized with 2-nitro-phenyl octyl ether that was responsive to cationic complexes formed between a dissolved metal ion and non-ionic surfactants in the sample [116]. At a later stage, they studied the effect of foreign species and elucidated the perturbation from ionic surfactants [117], which they eventually overcame by inserting an ion-exchange column into the base system [118]. 

The LFER approach of Abraham was the most powerful method to predict partition coefficients in varied experimental conditions (for example, see [68-72]). In particular, since 1,2-dichloroethane and o-nitrophenyl octyl ether are good experimental substitutes for alkane, in silico tools were developed with LFER equations to predict log Pdce [73] or log Pnpoe [74, 75]. 

In the same way, o-nitrophenyl octyl ether (o-NPOE) was immobilized on polycarbonate (PC) filters and the apparent permeability measured after 5 h incubation time was correlated to log Pnpoe for a series of reference compounds (log Pnpoe ranging from —1 to 3.6) [90]. Lipophilicity values in the alkane/water system were also determined using PAMPA with hexadecane-PC coated filters [89]. In this case, a correlation was found between intrinsic permeability (log Pq, permeability corrected for ionization and for unstirred water layer contribution, which particularly affects permeability of lipophilic compounds) and log P ik. However, log Pq is obtained from the knowledge of the pJC, value(s) and the permeability pH profile and therefore requires the full permeability pH profile to be measured for each compound, which negatively impacts the assay throughput. 

Liu, X., Bouchard, G., Girault, H.H., Testa, B. and Carrupt, P.A. (2003) Partition coefficients of ionizable compounds in o-nitrophenyl octyl ether/ water measured by the potentiometric method. Analytical Chemistry, 75, 7036-7039. 

Characterisation of the water/ o-nitrophenyl octyl ether system in terms of the partition of nonelectrolytes and of ions. Physical Chemistry Chemical Physics, 7, 2418-2422. 

The drug substance has been determined by direct potentiometric titration using chlorpromazine-sensitive electrodes [78. These consisted of an electroactive material in the membrane being either the chlorpromazine complex with either tetraphenylborate or dinonyinaphthalene sulfonate set in a PVC matrix. 2-nitrophenyl octyl ether was used as the plasticizer. 

The theories for the adsorption of mixtures of nonionic and ionic surfactants have been validated with tetraethylene glycol mono- -octyl ether (C8E4) and... 

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