Functional groups amino/amine

In each case, the N atom is sp hybridized, with one lone pair of electrons and three o-bonds. A quaternary ammonium ion is a tetrahedral ion of the form R4N, where as many as three of the R groups (which may all be different) can be replaced by H atoms. For example, the tetramethylammonium ion, (CH3)4N+, and the trimethylammonium ion, (CH3)3NH+, are quaternary ammonium ions. The amino group, the parent functional group of amines, is —NH2. 

In addition to carboxyl groups, amino acids have a second functional group, the amine group (NH2). Amines are related to ammonia (NH3). 

Amino acids contain both a basic functional group, the amine, and an acidic functional group, the carboxylic acid. Thus, they can undergo an internal acid-base reaction as shown in the following equation for die amino acid phenylalanine ... 

Derivatives of NH3,formed by replacing one or more H atoms with organic groups, R -> The amino group (-NH2) is the functional group of amines. 

The functional group of amines is the amino group (— NH2). The nitrogen atom undergoes sp3 hybridization and is attached to one or more carbon atoms. Amines can be classified as primary, secondary or tertiary amines depending upon the number of alkyl groups attached to the nitrogen atom. 

Figure 7.2 Examples of ROMP polymers containing functional groups, (a) Amine, (b) amino alcohol, and (c, d) amino acids.

Other immobilization methods are based on chemical and physical binding to soHd supports, eg, polysaccharides, polymers, glass, and other chemically and physically stable materials, which are usually modified with functional groups such as amine, carboxy, epoxy, phenyl, or alkane to enable covalent coupling to amino acid side chains on the enzyme surface. These supports may be macroporous, with pore diameters in the range 30—300 nm, to facihtate accommodation of enzyme within a support particle. Ionic and nonionic adsorption to macroporous supports is a gentle, simple, and often efficient method. Use of powdered enzyme, or enzyme precipitated on inert supports, may be adequate for use in nonaqueous media. Entrapment in polysaccharide/polymer gels is used for both cells and isolated enzymes. 

The carboxyl groups of amino acids undergo all the simple reactions common to this functional group. Reaction with ammonia and primary amines yields unsubstituted and substituted amides, respectively (Figure 4.9a,b). Esters... 

Most functional groups do not interfere with the diazotization reaction. Since aliphatic amines are stronger bases and therefore completely protonated at a pH < 3, it is possible that an aromatic amino group is converted into a diazonium group, while an aliphatic amino group present in the same substrate molecule is protected as ammonium ion and does not react. ... 

The hydrazinolysis is usually conducted in refluxing ethanol, and is a fast process in many cases. Functional groups, that would be affected under hydrolytic conditions, may be stable under hydrazinolysis conditions. The primary amine is often obtained in high yield. The Gabriel synthesis is for example recommended for the synthesis of isotopically labeled amines and amino acids. a-Amino acids 9 can be prepared by the Gabriel route, if a halomalonic ester—e.g. diethyl bromomalonate 7—is employed as the starting material instead of the alkyl halide ... 

Amines with more than one functional group are named by considering the -NH2 as an amino substituent on the parent molecule. 

Although a polyfunctional organic molecule might contain several different functional groups, we must choose just one suffix for nomenclature purposes. It s not correct to use two suffixes. Thus, keto ester 1 must be named either as a ketone with an -one suffix or as an ester with an -oate suffix but can t be named as an -onoate. Similarly, amino alcohol 2 must be named either as an alcohol (-0/) or as an amine (-amine) but can t be named as an -olamine or -anritiol. 

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