Scavenger ethyl alcohol

A test of the relative appropriateness of the curves in Figure 2 is the value of Gfi that each predicts. It appears that G(e soiv)o 4.0 in ethyl alcohol (16), so the predicted values of Gfi are 1.5 for Curve 1, 1.4 for Curve 2, 0.9 for 3 and 0.5 for 4. Many workers have experimentally estimated G/f = 1.0 in ethyl alcohol, and the results of a recent, more complete, scavenger study are consistent with a value of Gfi = 1.5 (16). It may therefore be concluded that the lifetime spectrum lies above Curve 3, and may be in the vicinity of Curve 2. 

A less plausible, but nevertheless not entirely unreasonable mechanism, which could account for these results would invoke an acid form for the OH radical which is not scavenged by ethyl alcohol. There is evidence (12) that this residual yield increases with decreasing pH in both the H202 photolysis and gamma radiolysis of RNO solutions which is not compatible with the above mechanism unless there is some acid-base equilibrium involving either the RN02H or C2H4OH radicals. 

Owing to its powerful Lewis acidity, BF3 is an effective reagent in organic synthesis, for example, promoting the conversion of alcohols and acids to esters, the polymerization of olefins and olefin oxides, and acylations and alkylations (in a manner similar to Friedel-Crafts processes). Mechanistic studies of some reactions of the latter type, such as the ethylation of benzene by QH5F, have shown that the BF3 functions as a scavenger for HF via the formation of HBF4 and thus participates stoichiometrically rather than catalytically. 

One of the most interesting papers on ascorbic acid-Cu reactions showed that ascorbic acid-Cu catalyzes the formation of ethylene from several precursors. The interest in ethylene was as an abscission agent in plants. All alcohols, aldehydes, acids, ethers, and epoxides formed ethylene when mixed with Cu and ascorbic acid in 5-mL closed bottles at 30 °C for 1 h. Methional was the most active, followed by propanal, propanol, propyl ether, ethyl ether, and ethanol. This reaction may be part of the oxygen scavenging system because Cu increases ascorbic acid s ability to scavenge oxygen. The authors claim this reaction cannot be attributed to copper in its lower valence state. 

AEPD AEPD 85 AI3-03358 Aminoethyl propanediol 2-Amino-2-ethylpropanediol 2-Amino-2-ethyl-1,3-propanediol EINECS 204-101-2 2-Ethyl-2-amino-propanediol NSC 8803 1,3-Propanediol, 2-amino-2-ethyl- AEPD -85 AEPD . Pigment dispersant, neutralizing amine, corrosion inhibitor, acid-salt catalyst, pH buffer, chemical and pharmxeutical intermediate and solubilizer. Chemical intermediate, formaldehyde scavenger, acid-salt catalyst for permanent-press resins, corrosion Inhibitor. Crystals mp = 37,5° bpto = 152-153° d = 1.0990 freely soluble In H2O soluble In alcohols pH 0.1,1M aqueous solution, Whittaker Clark Daniels. 

Methyl, ethyl, benzyl, benzhydryl, p-nitrobenzyl, p-methoxy-benzyl, 4-picolyl, j3j -trichloroethyl, j3-methylthioethyl, /J-p-toluenesulphonylethyl, and -p-nitrophenylthioethyl esters may be prepared directly from the acid and alcohol. TTie most usual method [4, 5] consists of heating the acid and an excess of the alcohol with an acid catalyst (e.g., Fischer-Speier, hydrochloric or sulphuric acid). The extent of reaction is improved if the water formed is removed by azeotropic distillation with an inert solvent (benzene, carbon tetrachloride, or chloroform). Considerable variation is possible in the natvire of the acid catalyst thus phosphoric acid [6], aryl sulphonic acids [7, 8, 9], alkyl sulphates [10], and acidic ion-exchange resins [11] may be employed. Removal of the water by azeotropic distillation during the formation of methyl esters is difficult and Brown and Lovette [12] introduced the novel reagent acetone dimethyl acetal (7) for the direct formation of methyl esters. In the presence of a trace of methanol and an acid catalyst the reagent acts as a scavenger of water formed by esterification and liberates further methanol for reaction. 

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