Methoxyethane

Ethers (R —O—R ). In substitutive nomenclature, one of the possible radicals, R—O—, is stated as the prefix to the parent compound that is senior from among R or R. Examples are methoxyethane for CH3OCH2CH3 and butoxyethanol for C4Hc,0CH2CH20H. 

Cyclic ethers are named either as heterocyclic compounds or by specialist rules of heterocyclic nomenclature. Radicofunctional names are formed by citing the names of the radicals R and R followed by the word ether. Thus methoxyethane becomes ethyl methyl ether and ethoxyethane becomes diethyl ether. 

Fig. 2. Chromatogram showing (a) the Ic separation of A, (+) (T)-(l-ferrocenyl-ethyl)thioethanol B, (+) 1-ferrocenyl-l-methoxyethane and C, (+) 1-mthenocenylethanol, on a 25-cm P-cyclodextrin column (see Table 2), and (b) the potential use of a P-cyclodextrin column to determine optical purity...

Under the best conditions, sodium cyclopentadienide gives pale yellow or orange solutions. Traces of air lead to red or purple solutions, as does insufficiently purified solvent, without, however, lowering the reaction yield appreciably. If 1,2-di-methoxyethane is used, in which sodium cyclopentadienide is less soluble than in tetrahydrofuran, white crystals may be obtained at this point. 

Chemical Name 2,2-dichloro-1,1-difluoro-1-methoxyethane Common Name 1,1-difluoro-2,2-dichloroethyl methyl ether Structural Formula GHjOCF CHCI ... 

Acetyl-2-Dimethylsulfamylthioxanthene A suspension of 2-dimethylsulfamylthioxanthene (12.22 grams, 0.04 mol) in 60 ml of dimethoxymethane is cooled to 0°C and 17.2 ml of a 2.91 M solution of n-butyl lithium in heptane is added slowly in a nitrogen atmosphere while the temperature is maintained below 10°C. After an additional 10 minutes of stirring, the cooling bath is removed and a solution of 2.96 grams of methyl acetate in 20 ml of di-methoxyethane is added during % hour and then the mixture is stirred at 25°C for an additional 3 hours. The reaction mixture is then treated with 60 ml of ethyl acetate and with 60 ml of a 10% aqueous ammonium chloride solution. The layers are separated and the ethyl acetate layer is washed once with water (25 ml) and then the solvent is removed by distillation. 

The extent to which 151 phosphorylates the aromatic amine in the phenyl ring is highly dependent upon the solvent. For instance, aromatic substitution of N-methylaniline is largely suppressed in the presence of dioxane or acetonitrile while pho.sphoramidate formation shows a pronounced concomitant increase. The presence of a fourfold excess (v/v) or pyridine, acetonitrile, dioxane, or 1,2-di-methoxyethane likewise suppresses aromatic substitution of N,N-diethylaniline below the detection limit. It appears reasonable to assume that 151 forms complexes of type 173 and 174 with these solvents — resembling the stable dioxane-S03 adduct 175 — which in turn represent phosphorylating reagents. They are, however, weaker than monomeric metaphosphate 151 and can only react with strong nucleophiles. 

In an attempt to approach a measure of tt-bonding in the Al-Al bond Uhl et al. examined the alkali metal reduction of tetrakis[bis(trimethylsilyl)methyl]dialane. Sodium or potassium reduction of [(Me3Si)2HC]2Al—Al[CH(SiMe3)2]2 in di-methoxyethane (DME) produced dark blue radical monoanions of [(Me3Si)2 HC]2A1—Al[CH(SiMe3)2]2 (Eq. 2).6... 

Amino-3-mercaptopropanoic acid, c411 1-Amino-2-methoxyethane, m77 a-(Aminomethyl)benzyl alcohol, a257... 

A. (R)-(-)-1 -Amino-1 -phenyl-2-methoxyethane (2).2 A solution of (R)-(-)-2-phenylglycinol (1) (25.0 g, 182.2 mmol) (Note 1) in anhydrous tetrahydrofuran (THF) (370 mL) (Note 2) is added dropwise via an oven-dried, 500-mL, pressure-equalizing addition funnel to an oven-dried, 2-L, round-bottomed flask containing a stirred (Note 3) suspension of potassium hydride (7.82 g, 195 mmol) (Note 4) in anhydrous THF (150 mL) at 25°C under an argon atmosphere. The resultant pale yellow mixture is stirred overnight and then treated dropwise with a solution of methyl iodide (25.2 g, 177.6 mmol) (Note 5) in THF (220 mL) over 2 hr at room temperature. The resultant mixture is stirred for an additional 3 hr, poured into cold ( 5°C) saturated aqueous sodium chloride solution (1.5 L) and extracted with anhydrous diethyl ether (4 x 250 mL) the combined organic extracts are dried over anhydrous sodium sulfate (Note 6). Filtration and rotary evaporation gives 39.2 g of yellow oil that is purified by vacuum distillation (bp 47-50°C, 0.2 mm) to yield 25.3 g (94%) of 2 as a colorless oil (Note 7). 

Using the same experimental approach, a family of enantiomerically pure oxonium ions, i.e., O-protonated 1-aryl-l-methoxyethanes (aryl = 4-methylphenyl ((5 )-49) 4-chlorophenyl ((5)-50) 3-(a,a,a-trifluoromethyl)phenyl ((5)-51) 4-(a,a,a-trifluoromethyl)phenyl ((S)-52) 1,2,3,4,5- pentafluorophenyl ((/f)-53)) and 1-phenyl-l-methoxy-2,2,2-trifluoroethane ((l )-54), has been generated in the gas phase by (CH3)2Cl -methylation of the corresponding l-arylethanols. ° Some information on their reaction dynamics was obtained from a detailed kinetic study of their inversion of configuration and dissociation. Figs. 23 and 24 report respectively the Arrhenius plots of and fc iss for all the selected alcohols, together with (/f)-40) of Scheme 23. The relevant linear curves obey the equations reported in Tables 23 and 24, respectively. The corresponding activation parameters were calculated from the transition-state theory. 

Fig. 24 Arrhenius plots for the dissociation of 0-protonated 1-aryl-1-methoxyethanes (aryl = 4-chlorophenyl ((5)-50) 3-(a,a,a-trifluoromethyl)phenyl ((5)-51) 4-(a,a,a-trifluor-omethyl)phenyl ((5 )-52) 1,2,3,4,5-pentafluorophenyl ((/ )-53) phenyl (i )-40)).

Table 23 Arrhenius parameters for the gas-phase intracomplex inversion of O-protonated 1-aryl-l-methoxyethanes...

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