Methyl iodide quaternary amine salt

Aminomethylated compounds (eqs. (15.13) and (15.16), Scheme 15.1) obtained by the Mannich reaction yield various kinds of 2-metalated compounds. The aminomethylated compounds yield quaternary amine salts by the Menshutkin reaction with an alkyl halide, and a methylol derivative is prepared by adding alkali to the salt. Dihydrocholesterol (cholestanol) reacts with dimethylamino-methylferrocene in the presence of methyl iodide and acetone to afford the ferrocene derivatives as shown in Scheme 15.5 [76,77],... 

Analytical methods iaclude thin-layer chromatography (69), gas chromatography (70), and specific methods for determining amine oxides ia detergeats (71) and foods (72). Nuclear magnetic resonance (73—75) and mass spectrometry (76) have also been used. A frequentiy used procedure for iadustrial amine oxides (77) iavolves titratioa with hydrochloric acid before and after conversion of the amine to the quaternary ammonium salt by reaction with methyl iodide. A simple, rapid quaHty control procedure has been developed for the deterrniaation of amine oxide and unreacted tertiary amine (78). 

To obtain the quaternary salt, furfuryl dimethyl amine so prepared is dissolved in dry benzene and to the solution is added slightly more than one equivalent of methyl iodide. Inducement of crystallization of the quaternary salt which separates may be effected as, for example, by scratching the side of the vessel containing the mixture or seeding with a small quantity of the crystalline quaternary salt. 

A thio-substituted, quaternary ammonium salt can be synthesized by the Michael addition of an alkyl thiol to acrylamide in the presence of benzyl trimethyl ammonium hydroxide as a catalyst [793-795]. The reaction leads to the crystallization of the adducts in essentially quantitative yield. Reduction of the amides by lithium aluminum hydride in tetrahydrofuran solution produces the desired amines, which are converted to desired halide by reaction of the methyl iodide with the amines. The inhibitor is useful in controlling corrosion such as that caused by CO2 and H2S. 

For example, Mannich reaction of N-methylpyrrole affords the corresponding dimethylaminomethyl derivative (2) and treatment with methyl iodide affords the quaternary salt (3). Displacement of the quaternary amine by means of cyanide leads to the substituted... 

Similar to other tertiary aliphatic amines, quinuclidine easily forms salts with mineral and organic acids, and quaternary derivatives with alkyl halides. However, the rates of reaction of alkyl iodides with quinuclidine are significantly higher than with tertiary aliphatic amines.32 For example, quinuclidine reacts with methyl iodide 50 times faster, and with isopropyl iodide 700 times faster, than does triethylamine. The addition compound of trimethylborane with quinuclidine is more stable than the corresponding adducts of tri-alkylamines. These results can be explained by the almost total... 

N-Methylation of secondary amines is usually accomplished either with CH20/HC02H (Leuckart/Clarke-Eschweiler reaction) or with CH20 followed by NaBH4 reduction. Methyl iodide treatment of secondary or tertiary bisben-zylisoquinoline alkaloids leads ultimately to the bis quaternary salts, and, in the presence of base, phenolic alkaloids are also O-alkylated. For example, lin-doldhamine (165) on treatment with ethyl bromide in 0.5 N ethanolic KOH gave the N,N,0,0,0-pentaethy 1 derivative (108, Section II,C,56) daurisoline was similarly permethylated with Mel and base (68, Section II,C,19). 

An amino group can be converted to a good leaving group by exhaustive methyla-tion, which converts it to a quaternary ammonium salt that can leave as a neutral amine. Exhaustive methylation is usually accomplished using methyl iodide. 

The reaction of a primary amine with nitrous acid to form a diazonium salt. (p. 910) Treatment of an amine with an excess of an alkylating agent (often methyl iodide) to form the quaternary ammonium salt. (p. 900)... 

Either the tertiary amine or the quaternary ammonium salt can be stored as a stable equivalent of the exo-methylene compound. In our first example, the Mannich base with dimethylamine is first methylated with methyl iodide and then added to the conjugate addition reaction. Elimination of trimethylamine, which escapes from the refluxing ethanol as a gas, reveals the exo-methylene ketone in which the methylene group is exo to a chain. Fast conjugate addition of the stabilized enolate of diethyl malonate produces the product. 

The dimethyl amine derivative produced was quaternized directly by methyl iodide, added slowly to a chilled solution of the ternary amine in ethyl acetate. When other ring substituents are present, the reductive eunination leads to isomeric configurations, as noted in Table I. Quaternary ammonium halide salts were characterized by melting point, TLC, or microanalytical data and and NMR. 

The alkylation of Schiff bases and hydrolysis of the resulting quaternary salts is an excellent method for obtaining certain secondary amines, RR NH, particularly where R = CHj. The procedure is less satisfactory for the introduction of large alkyl groups. The Schiff base is usually a derivative of benzaldehyde. It is readily prepared, and, without isolation, is alkylated furthermore, the salt is seldom isolated. An example is the treatment of the Schiff base from allylamine and benzaldehyde. Methyla-tion is accomplished by the action of methyl iodide at 80° for 16 hours subsequent hydrolysis furnishes methylallylamine in 71% yield. ... 

The main interest in steroidal tertiary amino-derivatives has centred on their quaternisation and Hofmann degradation. As part of an extensive study of amines of many types, McKenna found that equatorial amines react more rapidly than their axial epimers with methyl iodide [32], to give quaternary salts, although the situation was reversed at C( ) [33]. Steric hindrance from the C xs) position made the... 

Apart from the reactions of diazonium salts, a number of other reactions are known in which the C-N bond is broken. The best known of these is the Hofmann elimination of quaternary ammonium hydroxides (Scheme 2.37). An amine is converted by methylation with methyl iodide to the quaternary ammonium salt ( exhaustive methylation ). The iodide, on treatment with moist silver oxide, forms the quaternary ammonium hydroxide which undergoes a bimolecular elimination to form an alkene. The bimolecular elimination of onium salts yields the least alkylated alkene. This substitution pattern is determined by the ease with which a hydrogen atom can be attacked by the base. 

A Pyrrolidine is a secondary amine and reacts with two moles of methyl iodide to form a quaternary ammonium salt, compound A. The analytical data for compound B shows that it has one double bond equivalent which is present as an alkene. Consequently, compound B has been formed from compound A by a Hofmann elimination ... 

The formation of quaternary ammonium salts, followed by an elimination of the kind just described, is very useful in the determination of the structures of certain complicated nitrogen-containing compounds. The compound, which may be a primary, secondary, or tertiary amine, is converted into the quaternary ammonium hydroxide by treatment with excess methyl iodide and silver oxide. The number of methyl groups taken up by nitrogen depends upon the class of the amine a primary amine will take up three methyl groups, a secondary amine will take up two, and a tertiary amine only one. This process is known as exhaustive methylation of amines. 

Among the numerous derivatives useful in identifying amines are amides e.g., acetamides, benzamides, or sulfonamides) for primary and secondary amines quaternary ammonium salts (e.g., those from benzyl chloride or methyl iodide) or tertiary amines. 

Introduction, Amines are organic derivatives of ammonia, with one, two, or three hydrogen atoms replaced by an organic radical. The three types of amines, primary (RNHj), secondary (RjNH), and tertiary (R3N), may be prepared by the reaction of mono-halides with ammonia. In the case of reactive halides, like methyl iodide, the reaction proceeds to the formation of the quaternary salt— tetramethylammonium iodide ... 

When one mole of methyl iodide and four moles of ammonia are used, the formation of primary, secondary, and tertiary amines proceeds rapidly, so that within two minutes the formation of tetramethylammonium iodide assumes the dominant role of the reaction. About seventy-five per cent of the methyl iodide is converted to the quaternary salt, while the remainder forms a mixture of the three amines. The formation of the quaternary salt can be inhibited to a large extent by the addition of an ammonium salt, such as ammonium nitrate, which reacts with the free amino group of the amine to form the ion ... 

Treatment of the amine 14 (R = H) with sodium ethylacetamido-malonate gave the tryptophan analogue 17 on acid hydrolysis. Decarboxylation of the amino acid 17 in acetophenone gave the Schiff base 18, which was hydrolyzed by acid to the tryptamine analogue 19. Methylation of the amine 14 (R = H) with methyl iodide gave the quaternary salt 20,... 

In contrast to other methods for the methylation of primary amines, for example, the use of methyl iodide, this method leads to good yields of the iV,iV-dimethyl tertiary amines, without the formation of quaternary salt products.3 In comparison to reductive animation techniques, the reagents for the Eschweiler-Clarke reaction are cheap, and the reaction is easily scaled up.4... 

For the preparation of N-methylnonylamine this method proved the only practicable one 498 Nonylamine (9 g b.p. 85°/13 mm) is heated with benzaldehyde (7 g) for 1 h on a water-bath and the anil is distilled off in a vacuum (b.p. 179°/14mm). The anil obtained (13.6 g) is sealed with methyl iodide (8.4 g), set aside for 1 h and then heated for 3 h in a water-bath. The quaternary salt is precipitated as a deep red, viscous oil it is kept in 90% ethanol (40 ml) for 1 h on a water-bath, after which the alcohol is distilled off, the residue is acidified, and the benzaldehyde is extracted with ether. Treating the acid solution with base liberates the amine, which is separated and distilled (b.p. 95°/14 mm 6.6 g). 

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