Ethanolamines alkyl-substituted

For many years such media have been based on strong salt solutions, e.g. calcium chloride brines. Sodium dichromate has been used (seep. 17 26), but recently other inhibitors have been claimed to be effective. One patent quotes N-alkyl-substituted alkanolamines, e.g. 2-ethyl ethanolamine -I- BTA at pH A mixture of hydrazine hydrochloride -i- BTA has been claimed as well as a mixture of gelatin -h triethanolamine -h potassium dihydrogen phosphate . Other examples are to be found in the patent literature and the above are quoted to illustrate the diversity of chemicals that may be used. 

The rates of loss do not correlate with the rates of increase in the hydroxyl index for these systems or with the photoyellowing and uv phenomena. This indicates that the mechanism of oxidation of the amine functionality is complex. An additional feature of interest is the profile of this band loss as related to terminal amine structure. In the simple alkyl substituted systems namely diethyl, dimethyl and dibutyl there is an initial rapid loss followed by a slowing down of the rate of decrease on prolonged irradiation. However, with the oxygen containing systems namely morpholine, N-ethyl ethanolamine and N-methyl ethanolamine the rate of decrease is linear with irradiation time. Evidently, there must be two different mechanisms in operation here. The loss of these infra-red absorption bands may be due to a process of dealkylation via oxidation (see reactions later). The band situated at 2978 cm"l exhibited similar behaviour although the extent of the loss was less than that observed with the previous band and the order of rate loss was marginally different. 

A-Halogenoalkyl saccharins (56)103,153,200 are key intermediates for the preparation of symmetrically substituted ethylenediamines, ethanolamines, and homologs120 through direct exchange with an amine (57) or with acetate, in the latter case followed by Abe s procedure. (57) is also obtained from alkylation of 1 with alkyl or dialkylaminoalkyl halides.106,119. 

Ethylenimine is conveniently prepared from ethanolamine by heating the inner salt of the sulfate ester with aqueous alkali (37%). The method has been applied to other /3-amino alcohols to form the C-alkyl homologs of ethylenimine in which one to three of the four hydrogens may be substituted. The general procedure is illustrated by the synthesis of 2,2-dim ethyl ethylenimine (51%). The N-alkyl analogs can be made by treating the N-alkylethanolamine hydrochlorides with chlorosulfonic acid followed by the action of base on the intermediate sulfuric acid esters, as in the preparation of N-ethylethylenimine (70%). ... 

The rearrangement products derived from aromatic and non-aromatic heterocyclic amines crystallize readily from the lower alcohols. Unlike those of many of the A-substituted glycosylamines, the crystals are not solvated. On the other hand, the ketose derivatives of aralkyl- and alkyl-amines, such as 2-phenylethylamine, ethanolamine, diethanolamine, glycine ethyl ester, and phenylalanine (see Table II), are hydrated or alcoholated, or both, and are difficult to isolate in pure crystalline form. The crystals which have been isolated were hygroscopic. Alcohols, aqueous alcohols, and water are the most commonly used solvents for crystallization. Acetone, ether, or benzene have been added to the alcoholic media in order to increase the yield of crystalline compound. The use of solvents that contain peroxides promotes decomposition of the crystals during storage. ... 

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