Imidazoline reaction

Although acetonitrile is one of the more stable nitriles, it undergoes typical nitrile reactions and is used to produce many types of nitrogen-containing compounds, eg, amides (15), amines (16,17) higher molecular weight mono- and dinitriles (18,19) halogenated nitriles (20) ketones (21) isocyanates (22) heterocycles, eg, pyridines (23), and imidazolines (24). It can be trimerized to. f-trimethyltriazine (25) and has been telomerized with ethylene (26) and copolymerized with a-epoxides (27). 

The reaction of ethyleneimine with nittiles in the presence of HBF gives A -imidazolines (229). If trichloroacetonitrile [545-06-2] (R = Cl) is used as the nitrile component, the intermediate amidine can be isolated (230). 

Fats, Oils, or Fatty Acids. The primary products produced direcdy from fats, oils, or fatty acids without a nitrile iatermediate are the quatemized amidoamines, imidazolines, and ethoxylated derivatives (Fig. 3). Reaction of fatty acids or tallow with various polyamines produces the iatermediate dialkylarnidoarnine. By controlling reaction conditions, dehydration can be continued until the imidazoline is produced. Quaternaries are produced from both amidoamines and imidazolines by reaction with methyl chloride or dimethyl sulfate. The amidoamines can also react with ethylene oxide (qv) to produce ethoxylated amidoamines which are then quaternized. 

These compounds and their derivatives can be manufactured using relatively simple equipment compared to that required for the fatty nitrile derivatives. Cyclization of amidoamines to imidazolines requires higher reaction temperatures and reduced pressures. Prices of imidazolines are therefore high. 

Ammonium acetate and sodium methoxide are effective catalysts for the ammonolysis of soybean oil (49). Polyfunctional amines and amino alcohols such as ethylenediamine, ethanolamine, and diethanolamine react to give useful intermediates. Ethylenediamine can form either a monoamide or a diamide depending on the mole ratio of reactants. With an equimolar ratio of reactants and a temperature of >250° C, a cyclization reaction occurs to give imidazolines with ethylenediamine (48) ... 

Fabric Softeners, Surfactants and Bleach Activators. Mono- and bisamidoamines and their imidazoline counterparts are formed by the condensation reaction of one or two moles of a monobasic fatty acid (typically stearic or oleic) or their methyl esters with one mole of a polyamine. Imidazoline formation requires that the ethyleneamine have at least one segment in which a secondary amine group Hes adjacent to a primary amine group. These amidoamines and imidazolines form the basis for a wide range of fabric softeners, surfactants, and emulsifiers. Commonly used amines are DETA, TETA, and DMAPA, although most of the polyethylene and polypropane polyamines can be used. 

Many of the surfactants made from ethyleneamines contain the imidazoline stmcture or are prepared through an imidazoline intermediate. Various 2-alkyl-imidazolines and their salts prepared mainly from EDA or monoethoxylated EDA are reported to have good foaming properties (292—295). Ethyleneamine-based imida zolines are also important intermediates for surfactants used in shampoos by virtue of their mildness and good foaming characteristics. 2- Alkyl imidazolines made from DETA or monoethoxylated EDA and fatty acids or their methyl esters are the principal commercial intermediates (296—298). They are converted into shampoo surfactants commonly by reaction with one or two moles of sodium chloroacetate to yield amphoteric surfactants (299—301). The ease with which the imidazoline intermediates are hydrolyzed leads to arnidoamine-type stmctures when these derivatives are prepared under aqueous alkaline conditions. However, reaction of the imidazoline under anhydrous conditions with acryflc acid [79-10-7] to make salt-free, amphoteric products, leaves the imidazoline stmcture essentially intact. Certain polyamine derivatives also function as water-in-oil or od-in-water emulsifiers. These include the products of a reaction between DETA, TETA, or TEPA and fatty acids (302) or oxidized hydrocarbon wax (303). The amidoamine made from lauric acid [143-07-7] and DETA mono- and bis(2-ethylhexyl) phosphate is a very effective water-in-od emulsifier (304). 

Imidazoline-2-thione, 4,5-diphenyl-oxidation, 5, 405, 445 Imidazoline-2-thione, 4-methyl-Mannich reaction, S, 405 oxidation, 5, 445... 

S-group removal from, S, 445 oxidation, S, 445 reactions, S, 443-445 reactivity, 5, 375-376 synthesis, S, 493 Imidazoline-2-thiones Mannich reaction, 5, 405 reactions, 5, 102, 443-444 with alkynes, 5, 444 synthesis, S, 493... 

Imidazolinium perchlorate, 4-hydroxy-2,5,5-trimethyl-4-phenyl-synthesis, S, 487 Imidazolinium salts antistatic agents, 1, 409 Imidazolinium salts, 1-vinyl-polymerization, 1, 280 Imidazolin-2-one, 1-cyano-synthesis, S, 482 Imidazolin-2-one, 4,5-dialkyl-synthesis, S, 491 Imidazolin-2-one, 4,5-diaryl-bromination, S, 399-400 lmidazolin-2-one, 4,5-di( p-bromophenyl)-reactions... 

In these reactions, the formation of imidazoline and oxazoline rings corresponds to the reagent orientation previously observed for ynamines (84ZOR1648) and alkenylynamines (83ZOR926), as well as in their reactions with mononucleophiles such as amines (79ZOR1824 81ZOR1807) and alcohols (80ZOR1141). 

A rather simple derivative of imidazoimidazoline has been described as an antidepressant agent. Preparation of this compound starts with the displacement of the nitramine grouping in imidazoline derivative by phenyl ethanol amine The product of this reaction is then treated with thio-nyl chloride. The probable chloro intermediate ( ) cyclizes under the reaction conditions to afford imafen (5. ... 

The imidazoline denvative cibeiuoline (64) is a class I antiarrhythmic agent which has undergone clinical trials in the United States with apparently satisfactory results It is synthesized by diphenylcyclopropananon of acrylonitrile by thermal carbene generation from diphenyldiazo methane (62) to give 1 cyano 2,2 diphenylc>clopropane (63) Reaction of this with ethylenedia mine tosylate completes the synthesis of ciben/oline (64) [221... 

Most of the inhibitors in use are organic nitrogen compounds and these have been classified by Bregman as (a) aliphatic fatty acid derivatives, b) imidazolines, (c) quaternaries, (d) rosin derivatives (complex amine mixtures based on abietic acid) all of these will tend to have long-chain hydrocarbons, e.g. CigH, as part of the structure, (e) petroleum sulphonic acid salts of long-chain diamines (preferred to the diamines), (/) other salts of diamines and (g) fatty amides of aliphatic diamines. Actual compounds in use in classes (a) to d) include oleic and naphthenic acid salts of n-tallowpropylenediamine diamines RNH(CH2) NH2 in which R is a carbon chain of 8-22 atoms and x = 2-10 and reaction products of diamines with acids from the partial oxidation of liquid hydrocarbons. Attention has also been drawn to polyethoxylated compounds in which the water solubility can be controlled by the amount of ethylene oxide added to the molecule. 

Aziridines 180 (Scheme 3.65) react with acetonitrile and BF3 Et20, a Lewis catalyst, to give imidazolines 181 in 65-95% yield [98], Under the same reaction conditions, however, the C-3 phenyl-substituted aziridine 182 (Scheme 3.66) afforded oxazoline 183 in 59% yield [97]. 

A new entry to the 2,3-dihydroimidazo[l,2-c]pyrunidine system 18 is the reaction of N-acylimidates with imidazoline ketene aminals under focussed microwave irradiation <96SC453>. 

As yet, a number of experiments have failed to convert ureas 205 such as N-phenylurea or imidazolin-2-one by silylation amination with excess amines R3NHR4 such as benzylamine or morpholine and excess HMDS 2 as well as equivalent amounts of NH4X (for X=C1, I) via the silylated intermediates 206 and 207 in one reaction step at 110-150°C into their corresponding guanidines 208 with formation of NH3 and HMDSO 7 [35] (Scheme 4.13). This failure is possibly due to the steric repulsion of the two neighbouring bulky trimethylsilyl groups in the assumed activated intermediate 207, which prevents the formation of 207 in the equilibrium with 206. Thus the two step Rathke-method, which demands the prior S-alkylation of 2-thioureas followed by amination with liberation of alkyl-mercaptans, will remain one of the standard syntheses of guanidines [21, 35a,b,c]. 

The N-bis-silylated o-phenylenediamine 1511 reacts with DMF at 120°C to give benzimidazole, in 97% yield, and dimethylamine and hexamethyldisiloxane 7, whereas reaction of benzaldehyde with 1511 gives only 29% 2-phenylbenzimida-zole 1513, because the intermediate benzimidazoline 1512 is only rather slowly dehydrogenated to 1513 [52]. Heating of N,N -bis(trimethylsilyl)ethylenediamine 1514 with DMF affords imidazoline 1515 and dimethylamine and HMDSO 7 ]52] (Scheme 9.32). The lactam 1516 cycHzes analogously with SiCU 57/triethylamine in 63% yield to give 1517 ]53]. 

A Au mdssbauer study of reaction products of trimeric l-benzyl-2-gold(I)-imidazole leading to Au carbene or Au imidazoline complexes and trinuclear Au " imidazolyl derivatives. X-Ray crystal structure of [ (p-l-benzylimidazolato-N, C )Au 3l2j. Journal of Organometallic Chemistry, 470, 275-283. 

Polyesters may be used [27-30,223] instead of a fatty acid modifier for imidazoline. Thus a corrosion inhibitor with film-forming and film-persistency characteristics can be produced by first reacting, in a condensation reaction, a polybasic acid with a polyalcohol to form a partial ester. The partial ester is reacted with imidazoline or fatty diamines to result in a salt of the ester. Oil-soluble, highly water-dispersible corrosion inhibitor or oil-dispersible. 

Polyamides containing a-aminoacid units are readily obtained by reaction of bisazlactones (2-oxazolin-5-ones) with diamines. When polyamines such as diethylenetriamine (DETA) or triethylenetetramine (TETA) are used as the diamine component, the resultant polyamides readily cyclodehydrate above 200°C to produce polymers containing 2-imidazolin-5-one units in the backbone. Polyamides derived from simple diamines (e.g. 1,6-hexanedi amine) cyclodehydrate only in the presence of a suitable catalyst. Carboxylate salts and certain Lewis acids have been found to be efficient catalysts for this transformation. 

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