P-aminoethylations

The reaction of thioethers with ethyleneimine in the presence of acid yields sulfonium compounds. The reaction is reversible under alkaline conditions (125). Compounds in which double-bonded sulfur can exist in tautomerism with a form having a free SH group, such as thiourea (126,127), thiocarboxyhc acids (128), and thiophosphates (129), react to give aminoaLkylated products. The P-aminoethyl thiocarboxylate rearranges to give the amide. 

The Wenker aziridine synthesis entails the treatment of a P-amino alcohol 1 with sulfuric acid to give P-aminoethyl sulfate ester 2 which is subsequently treated with base to afford aziridine 3. Before the discovery of the Mitsunobu reaction, wbicb transforms an amino alcohol into an aziridine in one step under very mild conditions, the Wenker reaction was one of the most convenient methods for aziridine synthesis. However, due to the involvement of strong acid and then strong base, its utility has been limited to substrates without labile functionalities. 

In 1935, Wenker" first prepared P-aminoethyl sulfate ester (4, a solid) from thermal dehydration of monoethanolamine acid sulfate at 250°C according to Gabriel s procedure." Subsequently, the mixture of 4 and 40% NaOH aqueous solution was distilled. Further fractional distillation of the distillate in the presence of KOH and then Na at 55-56 C led to pure aziridine in 26.5% yield. 

Due to the convenience of the Wenker aziridine formation from P-aminoethyl sulfate ester (4) and base, many improvements ensued. Leighton et al. improved the yield of the first step for the formation of sulfate ester 4. First of all, both ethanolamine and 95% sulfuric acid were diluted with half of their weight of water and then slowly mixed together at 0 C. Finally, by keeping the temperature below 145 C, sulfate ester 4 was obtained in 90-95% yield. 

This class of aziridine-forming reaction includes the first reaction reported to afford aziridines. In 1888 Gabriel reported that aziridines could be prepared in a two-step process, by chlorination of ethanolamines with thionyl chloride, followed by alkali-induced cyclization [75]. Wenker subsequently reported that heating of 600 g of ethanolamine with more than 1 kg of 96 % sulfuric acid at high temperature produced P-aminoethyl sulphuric acid 282 g of it was distilled from aqueous base to give 23 g of aziridine itself, the first preparation of the parent compound in a pure condition [76]. Though there is no evidence to substantiate the hypothesis, the intermediate in these reactions is perhaps a cyclic sulfamidate (Scheme 4.51). 

Duchenne muscular dystrophy dimethyl formamide 5,5-dimethyl-1 -pyrroline-1 -oxide deoxynucleic acid diphenylene iodonium endothelium-derived relaxing factor epidermal growth factor early growth phase response gene ethyleneglycol- bis- (p- aminoethyl)-N,N,N, N -tetraacetic acid... 

Synonyms AI3-24219 2-Aminoethanol p-Aminoethyl alcohol BRN 0505944 Caswell No. 426 CCRIS 6260 Colamine EINECS 205-483-3 EPA pesticide chemicai code 011601 P-Ethanolamine Ethylolamine Glycinol 2-Hydroxyethylamine p-Hydroxyethylamine MEA Monoethanolamine Olamine Thiofalco M-50 UN 2491 USAF EK-1597. 

Aminoethanol, see Ethanolamine Aminoethene, see Ethylenimine p-Aminoethyl alcohol, see Ethanolamine p-Aminoethylamine, see Ethylenediamine Aminoethylene, see Ethylenimine Aminogen 11, see p-Phenylenediamine Aminomethane, see Methylamine l-Amino-2-methoxybenzene, see o-Anisidine l-Amino-4-methoxybenzene, see p-Anisidine 4-Aminomethoxybenzene, see p-Anisidine p-Aminomethoxybenzene, see p-Anisidine... 

Methyl pyrazine-2-carboxylic acid is refluxed with thionyl chloride in anhydrous benzene for approximately 12 hours. Benzene and thionyl chloride excess is removed by distillation. Then some anhydrous dioxane is added and this acid chloride solution is allowed to drop into p-(p-aminoethyl)-benzenesulfonamide suspension in dioxane and anhydrous pyridine. The resulting mixture is then refluxed for 3 hours. Dioxane is removed by distillation and then the residue is washed with water and acetic acid. The raw acylated sulfonamide is then filtered and crystallized from 95% ethanol, thus obtaining a product of MP 200° to 203°C. 

Methylisoxazole-3-carboxylic acid chloride 4-(p-Aminoethyl)benzene sulfonamide hydrochloride Chloroformic acid methyl ester N-Amino-hexamethyleneimine... 

There is obtained from 4-[p-[5-methyl-isoxazolyl-(3)-carboxamido]-ethyl]-benzene-sulfonamide (prepared from 5-methyl-isoxazole-(3)-carboxylic acid chloride and 4-(p-aminoethyl)benzene-sulfonamide hydrochloride, MP 213° to 214°C in pyridine) and chloroformic acid methyl ester, in a yield of 69%, the compound N-[[-4-[p-[5-methyl-isoxazolyl-(3)-carboxamido]-ethyl]]-benzene-sulfonyl]]-methyl-urethane in the form of colorless crystals of MP 173°C. 

A solution of 27 g of co-chloroacetopyrocatechol in 150 ml of ethyl alcohol is added dropwise within 2 hours into a stirred and refluxed solution of 81 g of 7-(p-aminoethyl)theophylline in 200 ml of a 60% aqueous ethyl alcohol. Following this, boiling is continued for another 3.5 hours while passing through nitrogen, and the precipitated product is separated by suction filtration, washed with water and dried. The product is suspended in alcohol, admixed with alcoholic hydrochloric acid while heating until an acid reaction is observed and subjected to suction filtration after cooling. Obtained in this manner are 37 g of 7-[p-(P -3,4-dihydroxyphenyl-p -... 

Synonym p-aminoethyl alcohol, ethylolamine, 2-hydroxyethylamine, p-hydroxyethylamine, monoethanolamine, MEA... 

WITTIG REAGENTS N-Alkyl-P-aminoethyl-phosphonium bromide. a-Formylethyl-idenetriphenyIphosphorane. N-PhenyI-keteniminyl(triphenyl)phosphorane. 

SYNS AMINOETHYLPIPERAZINE N-(P-AMINOETHYL)PIPERAZINE N-(2-AMINOETHYL)-PIPERAZINE l-(2-AMINOETHYL)PIPERAZINE USAF DO-46... 

SYNS AMINOETHYLETHANEDIAMIKE N-(2-AMINOETHYL)ETHYLENEDIAMINE 3-AZAPENT-ANE-l,5-DLAAflNE BIS(p-AMINOETHYL)AMINE BIS(2-AMINOETHYL)AMINE D.E.H. 20 DETA 2,2 -DIAMINODIETHYLAMINE 2,2 -MNOBISETHYL-AMINE... 

SYNS 4-(2-AMINOETHYL)DIETHYLENETRIAMINE DIETHYLENETRIAMINE, 4-(2-AMINOETHYL)- N,N-BIS(2-AMINOETHYL)-l,2-ETHANEDIAMINE 1,2-ETHANEDIAMINE, N,N-BIS(2-AADNOETHYL)- NITRILOTRIS(ETHYLAMINE) TREN TREN HP TRI(2-AMINOETHYL)AMINE 2,2, 2"-TRIAAnNO-TRIETHYLAMINE P,P, P"-TRIAinNOTRIETHYL-AMINE 2,2 ,2"-TRIAMINOTRIS(ETHYLAAnNE) TRIS(AMINOETHYL)AMINE TRIS(P-AMINOETHYL)AMINE... 

PYRIDAZINYL)BENZENESULFONAMIDE see SNJIOO a-AMINOETHYL ALCOHOL see AAG500 P-AMINOETHYL ALCOHOL see EEC600... 

BIS(2-AMINOETHYL)AMINE see DJG600 BIS(P-AMINOETHYL)ANnNE see DJG600 N,N -BIS(2-AMINOETHYL)-1.2-DIAMINOETHANE see TJROOO... 

The excellent adhesion of MS Polymer sealants to conventional construction substrates such as glass, metal, and plastics (e.g., PVC) is derived finm the widely used silane adhesion promoter V-(P-aminoethyl)-3-aminopropyltrimethoxysilane, DYNASYLAN DAMO-T. Another aspect of using a diaminosilane is the intrinsic change of pH that results in fast hydrolysis and condensation reactions of the MS Polymer . To guarantee a certain shelf life, MS Polymer sealants are generally formulated with vinyltrimethoxysilane, DYNASYLAN VTMO as a water scavenger. 

P-Aminoethyl alcohol colamine ethylolamine P-hydroxy-ethylamine 2-hydroxyethylamine. 

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