Primary amines with carboxylic acid salts

The catalysts for cationic polymerization can be strong anhydrous acids, Lewis acids, salts of primary and secondary amines, carboxylic acids, and salts of amines with carboxylic acids that split off water at elevated temperatures. The initiators react by coordinating with and fonrung rapid pre-equilibrium lactam cations. These cations are the reactive species in the polymerizations. Initiations of this type are also possible with weakly acidic compound, but such compounds ate not able to transfer protons to the lactam. They are capable, however, of forming hydrogen bonds with the lactams. The high reactivity of the lactam cations may be attributed to the decreased electron density at the carbonyl carbon atoms. This makes them more subject to nucleophilic attacks. Protonations of the amides occur at the oxygens, but small fractions of N-protonated amides are also presumed to exist in tautomeric equilibrium. To simplify the illustrations, all lactams will be shown in this section as... 

In base, primary amides hydrolyze to carboxylic acid salts and ammonia. The presence of ammonia (or amine from corresponding amides) can be detected similarly by odor or litmus. The carboxylic acid would be generated by neutralization with acid. 

Carbon dioxide and bicarbonate have very different chemical reactivities. CO2 is quite reactive toward nucleophiles (J), reacting, for example, with hydroxide to form bicarbonate, with ammonia and primary and secondary amines to form carbamates, with enolates to form carboxylic acids, and with a variety of organo-metallic compounds (e.g., Grignard reagents and organolithium reagents) to form carboxylic acid salts (i). Bicarbonate is much less reactive. 

Attempts have been made to rationalize the formation of different racemates by visualizing the crystal structures and calculating their lattice energies. Kinbara et al. [81] determined the crystal structures of a series of salts formed by chiral primary amines with achiral carboxylic acids. 

Kinbara, K. Hashimoto, Y. Sukegawa, M. Nohira, H. Saigo, K. Crystal structures of the salts of chiral primary amines with achiral carboxylic acids recognition of the common-occurring supramolecular assemblies of hydrogen-bond networks and their role in the formation of conglomerate. J. Am. Chem. Soc. 1996, 118, 3441-3449. 

List s group investigated a-benzoylo g lation of cyclic ketones and observed an improvement in selectivity when the Cinchona-derived primary amine, 9-amino-9-deo3q -epz-quinine 9-epi-QA) was used as a carboxylic acid salt. ° Thus, with 1.5 equivalents of benzoyl peroxide, various cyclic ketones were benzylojq lated in 45-81% yield (Scheme 15.24). The benzyloxylation of more challenging aldehydes and enals provided inferior results this time tri-chloroacetate was found to be more efficient than other acid salts tested. 

Tertiary amines also react with carboxylic acids to form an ammonium salt. Triethylamine (NEtg), for example, reacts with hexanoic acid to give an ammonium salt. Heating does not give an amide because there is no possibility for loss of water. Therefore, amides are formed only by heating the reaction products generated by mixing primary and secondary amines, or ammonia, with carboxylic acids. 

Amides can be hydrolysed by aqueous alkali or acid. With aqueous alkali the products are the salt of a carboxylic acid and a primary amine. With acid... 

Nickel peroxide is a solid, insoluble oxidant prepared by reaction of nickel (II) salts with hypochlorite or ozone in aqueous alkaline solution. This reagent when used in nonpolar medium is similar to, but more reactive than, activated manganese dioxide in selectively oxidizing allylic or acetylenic alcohols. It also reacts rapidly with amines, phenols, hydrazones and sulfides so that selective oxidation of allylic alcohols in the presence of these functionalities may not be possible. In basic media the oxidizing power of nickel peroxide is increased and saturated primary alcohols can be oxidized directly to carboxylic acids. In the presence of ammonia at —20°, primary allylic alcohols give amides while at elevated temperatures nitriles are formed. At elevated temperatures efficient cleavage of a-glycols, a-ketols... 

When carboxylic acids are treated with ammonia or amines, salts are obtained. The salts of ammonia or primary or secondary amines can be pyrolyzed to give... 

Use of the relatively small cyclopropane ring drastically reduces the potential for deleterious steric bulk effects and adds only a relatively small lipophilic increment to the partition coefficient of the drug. One of the clever elements of the rolicyprine synthesis itself is the reaction of d,l tranylcypromine (67) with L-5-pyrrolidone-2-carboxylic acid (derived from glutamic acid) to form a highly crystalline diastereomeric salt, thereby effecting resolution. Addition of dicyclohexylcarbodiimide activates the carboxyl group to nucleophilic attack by the primary amine thus forming the amide rolicyprine (68). 

The most characteristic reaction of butadiene catalyzed by palladium catalysts is the dimerization with incorporation of various nucleophiles [Eq. (11)]. The main product of this telomerization reaction is the 8-substituted 1,6-octadiene, 17. Also, 3-substituted 1,7-octadiene, 18, is formed as a minor product. So far, the following nucleophiles are known to react with butadiene to form corresponding telomers water, carboxylic acids, primary and secondary alcohols, phenols, ammonia, primary and secondary amines, enamines, active methylene compounds activated by two electron-attracting groups, and nitroalkanes. Some of these nucleophiles are known to react oxidatively with simple olefins in the presence of Pd2+ salts. Carbon monoxide and hydrosilanes also take part in the telomerization. The telomerization reactions are surveyed based on the classification by the nucleophiles. 

The solid state photochemistry of the salts of carboxylic acids with optically active primary amines has been studied111. Enantiomeric excesses ranging from 14-80% can be achieved (equation 59). 

Acid chlorides are very reactive, and they readily react with ammonia, primary amines, or secondary amines to form an amide. Figure 12-26 illustrates the reaction of an acid chloride with ammonia. Replacing one or two of the hydrogen atoms of ammonia with an organic group will result in an N-substituted amide. Tertiary amines react with acid chlorides to form a carboxylic acid and an ammonium salt. 

When carboxylic acids are treated with ammonia or amines, salts are obtained. The salts of ammonia or primary or secondary amines can be pyrolyzed to give amides,858 but the method is less convenient than 0-52, 0-53, and 0-55 and is seldom of preparative value.859 Lactams are produced fairly easily from -y- or 8-amino acids,860 e.g.,... 

The Feltzin mechanism 73) takes account of the presence of proton donors at the beginning of copolymerization. However, initiation probably proceeds in two ways 74) and depends on the type of the proton donor and its concentration in the copolymerization mixture. If HA in Eq. (45) is alcohol, phenol or moisture, initiation occurs according to Eq. (46), i.e. through interaction with the anhydride yielding an ammonium salt of the monoester. The formation of monoesters as primary active centres accounts here for the lower cocatalytic effect of phenols as compared with alcohols. If the proton donor is a carboxylic acid, activation of the tertiary amine (Eq. (63)) is followed by reaction with the epoxide according to Eq. (76)74. ... 

Bile acids, which have carboxylic acid groups at their side-chains, form salts with various amines. Salts of DCA and CA with various primary amines [23] show bilayer structures with a one-dimensional ladder hydrogen-bonding network. These salts act as host compounds and will include small alcohols. 

The 2,2,6,6-tetramethylpiperidinoxyl (TEMPO) radical was first prepared in 1960 by Lebedev and Kazarnovskii by oxidation of its piperidine precursor. TEMPO is a highly persistent radical, resistant to air and moisture, which is stabilized primarily by the steric hindrance of the NO-bond. Paramagnetic TEMPO radicals can be used as powerful spin probes for investigating the structure and dynamics of biopolymers such as proteins, DNA, and synthetic polymers by ESR spectroscopy [7]. A versatile redox chemistry has been reported for TEMPO radicals. The radical species can be transformed by two-electron reduction into the respective hydroxyl-amine or by two-electron oxidation into the oxoammonium salt [8]. One-electron oxidations involving oxoammonium salts have also been postulated [9]. The TEMPO radical is usually employed under phase-transfer conditions with, e.g., sodium hypochlorite as activating oxidant in the aqueous phase. In oxidations of primary alcohols carboxylic acids are often formed by over-oxidation, in addition to the de-... 

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