Alkylamination

A two-step procedure has been reported, in which the first step consisted of preforming an alkyl sodium amide, followed by attack of the alkyl amide on a pyridine ring at the 2-position with subsequent liberation of a hydride ion. The Sn(AE) mechanism, analogous to the standard Chichibabin reaction, is proposed 83EUP009170A2, 83USP4405790 87MIPI). In this manner, the reaction was cleaner and the yields were better than under the conditions of Vajda and Kovacs, in which the heterocycle and alkylamine were required to react simultaneously with alkali metals, thus yielding appreciable amounts of dimers and tarry materials. 

Primary alkylamines are extremely difficult to metallate with sodium amide or sodium hydride and generally do not react with metallic sodium. It is known that the amines react quickly and smoothly under mild conditions with potassium hydride, but from a practical viewpoint, metallation with sodium would be preferred (73JA982). A new catalytic procedure has made it possible to prepare alkyl sodium amides in good yields and in reasonable time. The 

---

Amines are named m two mam ways m the lUPAC system either as alkylamines or as alkanamines When primary amines are named as alkylamines the ending amine IS added to the name of the alkyl group that bears the nitrogen When named as alkan amines the alkyl group is named as an alkane and the e ending replaced by amine... 

Give an acceptable alkylamine or alkanamine name for each of... 

Arylamines Aniline like alkylamines has a pyramidal arrangement of bonds around nitrogen but its pyramid is somewhat shallower One measure of the extent of this flat tenmg is given by the angle between the carbon-nitrogen bond and the bisector of the H—N—H angle... 

A collection of physical prop erties of some representative amines is given in Appendix 1 Most commonly encoun tered alkylamines are liquids with unpleasant fishy odors... 

We have often seen that the polar nature of a substance can affect physical properties such as boiling point This is true for amines which are more polar than alkanes but less polar than alcohols For similarly constituted compounds alkylamines have boiling points higher than those of alkanes but lower than those of alcohols... 

Just as aniline is much less basic than alkylamines because the unshared electron parr of nitrogen is delocalized into the tt system of the nng p nitroamlme is even less basic because the extent of this delocahzahon is greater and involves the oxygens of the nitro group... 

Nonaromatic heterocyclic compounds piperidine for example are similar m basic ity to alkylamines When nitrogen is part of an aromatic ring however its basicity decreases markedly Pyridine for example resembles arylammes m being almost 1 mil lion times less basic than piperidine... 

Alkylamines are in principle capable of being prepared by nucleophilic substitution reactions of aUtyl halides with ammonia... 

A method that achieves the same end result as that desired by alkylation of ammonia but which avoids the formation of secondary and tertiary amines as byproducts is the Gabriel synthesis Alkyl halides are converted to primary alkylamines without contam mation by secondary or tertiary amines The key reagent is the potassium salt of phthal imide prepared by the reaction... 

Both alkylamines and arylamines undergo these reactions... 

Figure 22 5 shows what happens when a typical primary alkylamine reacts with nitrous acid Because nitrogen free products result from the formation and decomposition of diazonium ions these reactions are often referred to as deamination reactions Alkyl... 

Section 22 1 Alkylamines are compounds of the type shown where R R and R" are alkyl groups One or more of these groups is an aryl group m arylammes... 

Alkylamines are named m two ways One method adds the ending amine to the name of the alkyl group The other applies the principles of sub stitutive nomenclature by replacing the e ending of an alkane name by amine and uses appropriate locants to identify the position of the ammo group Arylammes are named as derivatives of aniline... 

Ammonia can act as a nucleophile toward primary and some secondary alkyl halides to give primary alkylamines Yields tend to be modest because the primary amine IS itself a nucleophile and undergoes alkylation Alkylation of ammonia can lead to a mixture containing a primary amine a secondary amine a tertiary amine and a quaternary ammonium salt... 

Alkylation of phthalimide The Gabriel synthesis (Section 22 8) The potassium salt of phthalimide reacts with alkyl hal ides to give N alkylphthalimide deriva fives Hydrolysis or hydrazinolysis of this derivative yields a primary alkylamine... 

Alkyl azides prepared by nucleophilic substitution by azide ion in primary or secondary alkyl halides are reduced to primary alkylamines by lithium aluminum hydride or by catalytic hydrogenation... 

Tertiary alkylamines illustrate no useful chemistry on nitrosation Tertiary aryl-amines undergo nitrosation of the ring by electrophilic aromatic substitution... 

Secondary alkylamines and secondary arylamines y e d N nitroso amines... 

Tetrahydroisoqumoline is a stronger base than tetrahydroquinohne The unshared electron pair of tetrahydroquinohne is delocalized into the aromatic nng and this substance resembles am line m its basicity whereas tetrahydroisoqumoline resembles an alkylamine... 

Gabriel synthesis (Section 22 8) Method for the synthesis of primary alkylamines in which a key step is the formation of a carbon-nitrogen bond by alkylation of the potassium salt of phthalimide... 

Primary amine (Section 22 1) An amine with a single alkyl or aryl substituent and two hydrogens an amine of the type RNH2 (pnmary alkylamine) or ArNH2 (primary aryl amine)... 

Acetaldehyde, first used extensively during World War I as a starting material for making acetone [67-64-1] from acetic acid [64-19-7] is currendy an important intermediate in the production of acetic acid, acetic anhydride [108-24-7] ethyl acetate [141-78-6] peracetic acid [79-21 -0] pentaerythritol [115-77-5] chloral [302-17-0], glyoxal [107-22-2], aLkylamines, and pyridines. Commercial processes for acetaldehyde production include the oxidation or dehydrogenation of ethanol, the addition of water to acetylene, the partial oxidation of hydrocarbons, and the direct oxidation of ethylene [74-85-1]. In 1989, it was estimated that 28 companies having more than 98% of the wodd s 2.5 megaton per year plant capacity used the Wacker-Hoechst processes for the direct oxidation of ethylene. 

Simple alkyl and alkenyl ethers of pentaerythritol are produced on direct reaction of the polyol and the requited alkyl or alkenyl chloride in the presence of quaternary alkylamine bromide (44). AHyl chloride produces the pentaerythritol tetraHyl ether [1471 -18-7],... 

The latest of three ethylene recovery plants was started in 1991. Sasol sold almost 300,000 t of ethylene in 1992. Sasol also produces polypropylene at Secunda from propylene produced at Sasol Two. In 1992 Sasol started constmction of a linear alpha olefin plant at Secunda to be completed in 1994 (40). Initial production is expected to be 100,000 t/yr pentene and hexene. Sasol also has a project under constmction to extract and purify krypton and xenon from the air separation plants at Sasol Two. Other potential new products under consideration at Sasol are acrylonitrile, acetic acid, acetates, and alkylamines. 

The prototype of a pure ethylenediamine is tripeleimamine antazoline [91-75-8] C27H22N2, belongs to the same family of compounds. Several well-known alkylamines in addition to chlorpheniramine are known. Hexchlorpheniramine maleate [2438-32-6] and triprohdine monohydrochloride monohydrate [6138-79-0] an alkenyl derivative, are two examples. 

The resihency and dyeabihty of poly(vinyl alcohol) fibers is improved by a process incorporating -hydroxybenzaldehyde to provide a site for the formation of a stable Mannich base. Hydroxyl groups on the fiber are converted to acetal groups by -hydroxybenzaldehyde. Subsequent reaction with formaldehyde and ammonia or an alkylamine is rapid and forms a stable Mannich base that is attached to the polymer backbone (94). 

---