Amination alkylamination

Nitrogen s unshared electron pair is of major importance in understanding the structure and properties of amines. Alkylamines have a pyramidal arrangement of bonds to nitrogen, and the unshared electron pair... 

There are 49 different formulations available in the United States, including 2,4-D salts (sodium, amine, alkylamine, and alkanolamine) and esters (propanoic acid, butanoic acid, and other alkoxy compounds). Concentrated fomiulations of 2,4-D esters are likely to contain petroleum solvents (identified on the first aicT statement on the pesticide label) while these are considered inert ingredients because they are not pesticides, they may have their own innate toxicity (see Toluene and Xylene, p 357 and Hydrocarbons, p 219). 

Organic Low-molecular-weight amines, alkylamines, mono-, di-, tri-. Cation Suppressed and non-... 

The latest development in carboxylic-based weak acid cation exchangers are columns designed for the determination of hydrophobic and polyvalent amines, including biogenic amines, alkylamines, and diamines, using simple aqueous eluent and elevated column temperature. 

Amines Alkylamines/M"" - montmorillonites Proton ttansfer, ion dipole, and/or coordination Fripiatet al. (62)... 

Strongly basic amines (alkylamines, pK 3—6) react with syn,syn-l 5-dimethylpentadienyliron tricarbonyl to give cw,tra/M -dienylamines, but weakly basic amines (arylamines, pKi> ca. 10) react with inversion to give /ran5,tra/tr-dienylamines. The best explanation of this difference is that product control is kinetic for the strong bases, thermodynamic for the weak ones. ... 

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... 

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... 

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... 

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... 

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... 

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)... 

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. 

Thermodynamic data are available only for the lower alkylamines, mainly estimates based on a few experimental deterrninations (3,4). Many manufacturing processes appear to be limited by thermodynamic equiUbria. The lack of accurate free energy data for these amines limits the appHcation of thermodynamic considerations, in contrast to the situation in hydrocarbon technology. 

AUylamines are somewhat unique in that both amine and olefin functionahties are available. This allows the aHylamines to find uses in many areas where the simpler aLkylamines are not suitable, eg, taking advantage of the double bond to form polymeric ammonium salts used as flocculating agents (see... 

ALkylamines are corrosive to copper, copper-containing alloys (brass), aluminum, 2inc, 2inc alloy, and galvani2ed surfaces. Aqueous solutions of aLkylamines slowly etch glass as a consequence of the basic properties of the amines in water. Carbon or stainless steel vessels and piping have been used satisfactorily for handling aLkylamines and, as noted above, some aLkylamines can act as corrosion inhibitors in boiler appHcations. 

Lower aHphatic amines can be prepared by a variety of methods, using many different types of raw materials. By far the largest commercial appHcations involve the reaction of alcohol with ammonia to form the corresponding amines. Other methods are employed depending on the particular amine desired, raw material availabiHty, plant economics, and the abiHty to seU co-products. The foUowing manufacturing methods are used commercially to produce the lower aLkylamines. Table 5 gives plant and capacity information for these methods. 

Method 7. Alkyl haHde amination reaction of ammonia or alkylamine with an alkyl haHde. 

To manufacture the lower aLkylamines by Method 1, ammonia and alcohol are passed continuously over a fixed bed containing the catalyst in a gas—soHd heterogeneous reaction. The ammonia to alcohol mole ratio varies from 2 1 to 6 1 depending on the amine desired as shown in Figure 1. Operating conditions are maintained in the range from 300—500°C and 790—3550 kPa (100—500 psig) at a gas hourly space velocity between 500—1500 vol/vol per hour. Yields are typically in excess of 90%. 

Olefin Amination (Method 6). The most recent technology for the production of lower alkylamines is olefin amination (14). This is 2eohte-cataly2ed reaction of ammonia with an olefin, eg, isobutylene, and is practiced in a packed-bed reactor system in the vapor phase. 

Reductive amination of cyclohexanone using primary and secondary aHphatic amines provides A/-alkylated cyclohexylamines. Dehydration to imine for the primary amines, to endocycHc enamine for the secondary amines is usually performed in situ prior to hydrogenation in batch processing. Alternatively, reduction of the /V-a1ky1ani1ines may be performed, as for /V,/V-dimethy1 cyclohexyl amine from /V, /V- di m e th y1 a n i1 i n e [121 -69-7] (12,13). One-step routes from phenol and the alkylamine (14) have also been practiced. 

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