Nitrogens tertiary

Tertiary amine (Section 22 1) Amine of the type R3N with any combination of three alkyl or aryl substituents on nitrogen Tertiary carbon (Section 2 13) A carbon that is directly at tached to three other carbons... 

Increased substitution on the nitrogen tertiary amines interact more strongly than secondary amines, which interact more strongly than primary amines, presumably because of the electron donating ability of alkyl groups... 

The acid-catalyzed hydrolysis of aziridines is usually of little preparative value. In certain instances such a reaction may represent the final step in the isomerization of a jB-anaino aloolhoJai8 a4D (Eq. d). Kinetic studies show that when a nitrogen-tertiary carbon bond is present in the axiridine, this bond is hydrolyzed in an 5 1-type reaction318 [Pg.282]

Despite the differences in final product, the reaction of nitrous acid with all these amines involves the same initial step electrophilic attack by NO with displacement o/H This attack occurs at the position of highest electron availability in primary and secondary amines at nitrogen. Tertiary aromatic amines are attacked at the highly reactive ring. 

Figure 10.3-40. The rating for the disconnection strategy carbon-heteroatom bonds is illustrated, Please focus on the nitrogen atom of the tertiary amino group. It is surrounded by three strategic bonds with different values. The low value of 9 for one ofthese bonds arises because this bond leads to a chiral center. Since its formation requires a stereospecific reaction the strategic weight of this bond has been devalued. In contrast to that, the value of the bond connecting the exocyclic rest has been increased to 85, which may be compared with its basic value as an amine bond.

They are readily hydrolysed by boiling dilute hydrochloric acid and the original amine can be recovered by neutralisation with alkali and steam distillation. Primary aliphatic amines liberate nitrogen with nitrous acid whilst tertiary amines are unaffected. 

The imides, primaiy and secondary nitro compounds, oximes and sulphon amides of Solubility Group III are weakly acidic nitrogen compounds they cannot be titrated satisfactorily with a standard alkaU nor do they exhibit the reactions characteristic of phenols. The neutral nitrogen compounds of Solubility Group VII include tertiary nitro compounds amides (simple and substituted) derivatives of aldehydes and ketones (hydrazones, semlcarb-azones, ete.) nitriles nitroso, azo, hydrazo and other Intermediate reduction products of aromatic nitro compounds. All the above nitrogen compounds, and also the sulphonamides of Solubility Group VII, respond, with few exceptions, to the same classification reactions (reduction and hydrolysis) and hence will be considered together. 

The amine must be primary (RNH2) or secondary (R2NH) Tertiary amines (R3N) can not form amides because they have no proton on nitrogen that can be replaced by an acyl group... 

Unlike alcohols and alkyl halides which are classified as primary secondary or tertiary according to the degree of substitution at the carbon that bears the functional group amines are classified according to their degree of substitution at nitrogen An amine with... 

Secondary and tertiary amines are named as N substituted derivatives of primary amines The parent primary amine is taken to be the one with the longest carbon chain The prefix N is added as a locant to identify substituents on the ammo nitrogen as needed... 

The preparation of amines by the methods described m this section involves the prior synthesis and isolation of some reducible material that has a carbon-nitrogen bond an azide a nitrile a nitro substituted arene or an amide The following section describes a method that combines the two steps of carbon-nitrogen bond formation and reduction into a single operation Like the reduction of amides it offers the possibility of prepar mg primary secondary or tertiary amines by proper choice of starting materials... 

The shape of a large protein is influenced by many factors including of course Its primary and secondary structure The disulfide bond shown m Figure 27 18 links Cys 138 of carboxypeptidase A to Cys 161 and contributes to the tertiary structure Car boxypeptidase A contains a Zn " ion which is essential to the catalytic activity of the enzyme and its presence influences the tertiary structure The Zn ion lies near the cen ter of the enzyme where it is coordinated to the imidazole nitrogens of two histidine residues (His 69 His 196) and to the carboxylate side chain of Glu 72... 

Tertiary amine exchangers possess —R3NH2 groups which have exchanging properties only in an acidic medium when a proton is bound to the nitrogen atom. 

The polymerization of ethyleneimine (16,354—357) is started by a catalyticaHy active reagent (H or a Lewis acid), which converts the ethyleneimine into a highly electrophilic initiator molecule. The initiator then reacts with nitrogen nucleophiles, such as the ethyleneimine monomer and the subsequendy formed oligomers, to produce a branched polymer, which contains primary, secondary, and tertiary nitrogen atoms in random ratios. Termination takes place by intramolecular macrocycle formation. 

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