Alkyl, amines Table

Despite the vivid 27 kcal mol-1 variation in TB splitting (Ae , dashed line) in Fig. 3.72(a), the total energy (Eioi, solid line) exhibits only the typical 2 kcal mol-1 variations of an ordinary alkyl amine (Table 3.23). Thus, the variations in Ae do not seem to reflect significant variations in stability or localization of the parent neutral species. 

The ammonium ions of most alkyl amines are characterized by a pA value between 10 and 11, but aryl amines are very different. Ammonium ions of aryl amines are more acidic (lower piQ than the ammonium ion of alkyl amines (Table 23.2). In other words, aryl amines are less basic. This can be rationalized by considering the delocalized nature of the lone pair of an aryl amine ... 

The effect of chain length is more pronounced in the tertiary alkyl-amines (Table 4), where triethylamine is much more basic than trimethylamine, whilst iV,i T-dimethylethylamine and iV,iV-diethyl-methylamine lie intermediately. There are some anomalies amongst the data for the higher members of this series, and further measurements on them would be of interest. 

Semipermanent hair color products are formulated at an alkaline pH, usually between 8.5 and 10. At this pH the cuticle of the hair lifts away from the hair a Httie, allowing for easier penetration of dye. An alkyl amine buffered with an organic acid normally is used to obtain the desired pH. The formulations contain a mixture of solvents and surfactants to solubilize the dyes and a thickening agent is added so that the product stays on the hair without mnning or dripping. A 20—30 min appHcation time is normal for this type of product. A representative formula for a semipermanent dye product is given in Table 7. 

Wetting times of /V,/V-dimethy1-/ -alkyl amine oxides as a function of the alkyl chain length show a minimum with dimethyl dodecyl amine oxide (Table 3). Foam generation of dimethyl-/ -alkylamine oxides solutions show a maximum when the alkyl group contains 14 carbons. 

Ethoxylation of alkyl amine ethoxylates is an economical route to obtain the variety of properties required by numerous and sometimes smaH-volume industrial uses of cationic surfactants. Commercial amine ethoxylates shown in Tables 27 and 28 are derived from linear alkyl amines, ahphatic /-alkyl amines, and rosin (dehydroabietyl) amines. Despite the variety of chemical stmctures, the amine ethoxylates tend to have similar properties. In general, they are yellow or amber Hquids or yellowish low melting soHds. Specific gravity at room temperature ranges from 0.9 to 1.15, and they are soluble in acidic media. Higher ethoxylation promotes solubiUty in neutral and alkaline media. The lower ethoxylates form insoluble salts with fatty acids and other anionic surfactants. Salts of higher ethoxylates are soluble, however. Oil solubiUty decreases with increasing ethylene oxide content but many ethoxylates with a fairly even hydrophilic—hydrophobic balance show appreciable oil solubiUty and are used as solutes in the oil phase. 

Commercial Antioxidants Table 4 includes the main classes of antioxidants sold in the United States and the suppHer s suggested apphcations. Some of these are mixtures rather than single substrates. This is especially tme of alkylated amines and alkylated phenols. The extent of alkylation and the olefins used for alkylation can vary among manufacturers. Table 4 is not a complete listing of available antioxidants in the United States. 

Since the order of increasing CL intensity for alkyl amines reacted with Ru(bpy)32+ is tertiary amines > secondary amines > primary amines, pharmaceutical compounds bearing a tertiary amine function (e.g., antihistamine drugs [99], anticholinergic drugs [100], erythromycin [101], and its derivatives [102]) have been sensitively determined after HPLC separation (Table 3). The method was applied to the detection of d- and L-tryptophan (Trp) after separation by a ligand-exchange HPLC [103], The detection limits for d- and L-Trp were both 0.2 pmol per injection. Oxalate in urine and blood plasma samples has also been determined by a reversed-phase ion-pair HPLC (Fig. 18) [104], Direct addition of... 

A variety of alkyl amines B, including 1-propylamine, ethylene diamine, 1,3-diaminopropane, and (7 )-l-amino-2-propanol have been used as reactants. The guest exchange kinetic results are reported in Table 13. The presence of more than one reacting [/3-CD-H-A] structure is observed with A = DOPA and penicillamine. The results have been rationalized in terms of specific interactions in the relevant inclusion complexes which determine their structure and relative stability. 

The usefulness of this reaction for the preparation of heterocycles under mild conditions became apparent in 1978, when chemists from Merck, Sharp Dohme reported the synthesis of bicyclic 3-lactams by intramolecular carbene N-H insertion [1179]. Intramolecular N-alkylation of P-lactams by carbene complexes is one of the best methods for preparation of this important class of antibiotic and many P-lactam derivatives have been prepared using this methodology [1180 -1186] (Table 4.11). Intramolecular N-H insertion can also be used to alkylate amines [1187-1189], y-lactams [1190], and carbamates [1191-1193] (Table 4.11). 

Table 24 Amidation of unactivated esters with alkyl amines...

Table 6.23 gives the rate constants for the reactions of OH and 03 with some simple alkyl amines at room... 

TABLE 6.23 Room Temperature Rate Constants and Estimated Atmospheric Lifetimes for the Gas-Phase Reactions of Some Alkyl Amines and Amides with OH and 03b... 

Merrifield resin [33-37] and other support-bound benzyl halides [38] have also been used to alkylate amines (Entries 5-10, Table 10.2). Similarly, resin-bound allyl bromides react cleanly with aliphatic or aromatic amines (Entry 16, Table 10.2). Entry 15 in Table 10.2 is a rare example of the N-alkylation of an amine under the conditions... 

The method involves chromatographic separation of water soluble analytes and detection of separated ions by a conductivity detector. It can also be used to analyze oxyhalides, such as perchlorate (C104) or hypochlorite (CIO) weak organic acids, metal ions, and alkyl amine. The analytes that can be determined by ion chromatography are listed in Table 1.11.1. 

Matsushita et al. (2007) subsequently demonstrated the ability to N-alkylate amines (Scheme 57) under continuous flow, again employing a quartz microreaction channel coated with a Ti02 or Pt-loaded Ti02 layer. As Table 28 illustrates, the illuminated specific surface area per unit of liquid attained within a microchannel is large even without taking into account the surface roughness of the catalyst however, it can be seen that a shallow reaction channel provides optimal photon efficiency. 

As mentioned before, acyclic substrates have been studied in detail, in particular, the reactions of 1,3-diphenylpropenyl ester (19, X=COR) or carbonate (19, X=OCC>2R), the gold standard for this class. Selected ligands for the allylic alkylation, amination, and etherification are shown in Fig. 1 and representative data are presented in Table 1. 

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. ... 

Table VIll.—Homologous Series of Alkyl Amines...

A few examples of alkylative amination of aldehydes are reported in Table 16. ... 

Table 16 Alkylative Amination of Various Aldehydes by RTi(NEt2)3...

As indicated in Table 24.1, arylamines are generally less basic than alkyl-amines. Anilinium ion has pX = 4.63, for instance, whereas methylammo-nium ion has pK, = 10.66. Arylamines are less basic than alkylamines because the nitrogen lone-pair electrons are delocalized by interaction with the aromatic ring v electron system and are less available for bonding to H. In resonance terms, arylamines are stabilized relative to alkylamines because of the five resonance structures ... 

---