Primary and secondary amines

Amines. Primary and secondary aUphatic amines also yield carbamates in the presence of excess amine or other acid acceptors such as inorganic bases. Aromatic primary and secondary amines and heterocycHc amines react similarly, although slowly. 

Lithium aluminum hydride (LiAlH4) is the most powerful of the hydride reagents. It reduces acid chlorides, esters, lactones, acids, anhydrides, aldehydes, ketones and epoxides to alcohols amides, nitriles, imines and oximes to amines primary and secondary alkyl halides and toluenesulfonates to... 

Regioselective bromination of phenols gave 2-bromo-, 4-bromo-, 2,6-dibromo-, 2,4-dibromo, 2-bromo-6-substituted, 4-bromo-2-substituted and 2,4-dibromo-6-substitutgd phenols, respectively. Especially, 2-bromo-, 2,6-dibromo- and 2-bromo-6-substituted phenols which were prepared via long steps, were obtained in NBS-amine (primary and secondary) system in high yields under ordinary conditions. The scope and their mechanisms were discussed. 

Pr)4, " borohydride-exchange resin,and formic acid. When the last is used, the process is called the Wallach reaction. Conjugated aldehydes are converted to alkenyl-amines with the amine/silica gel followed by reduction with zinc borohydride.In the particular case where primary or secondary amines are reductively methylated with formaldehyde and formic acid, the method is called the Esch-weiler-Clarke procedure. It is possible to use ammonium (or amine) salts of formic acid, " or formamides, as a substitute for the Wallach conditions. This method is called the Leuckart reaction,and in this case the products obtained are often the N-formyl derivatives of the amines instead of the free amines. Primary and secondary amines can be iV-ethylated (e.g., ArNHR ArNREt) by treatment with NaBH4 in acetic acid. Aldehydes react with aniline in the presence of Mont-morillonite KIO clay and microwaves to give the amine. Formaldehyde with formic acid converts secondary amines to the N-methyl derivative with microwave irradiation. 

Amines (primary and secondary aromatic) / -Chloranil The reaction depends on the catalytic effect of silica gel. Monochlorobenzene, as solvent for the reagent, also contributes. There is no reaction on cellulose layers. [17, 22]... 

SNAr substitutions of activated aromatic halides, especially aromatic fluorides, provide useful means for the construction of aromatic diethers or amines. Primary and secondary amines react with l, 2-dihalo-4,5-dinitrobenzene to give nitro group substitution at room temperature. The halogen substituents on the ring remain unsubstituted and can be used in further transformation (Eq. 9.5).8... 

Suitable curatives for the polysulfide-epoxy reaction include liquid aliphatic amines, liquid aliphatic amine adducts, solid amine adducts, liquid cycloaliphatic amines, liquid amide-amines, liquid aromatic amines, polyamides, and tertiary amines. Primary and secondary amines are preferred for thermal stability and low-temperature performance. Not all amines are completely compatible with polysulfide resins. The incompatible amines may require a three-part adhesive system. The liquid polysulfides are generally added to the liquid epoxy resin component because of possible compatibility problems. Optimum elevated-temperature performance is obtained with either an elevated-temperature cure or a postcure. 

Amines. Primary and secondary amines, both of the aliphatic and aromatic series, react vigorously with phenyl dichloroarsine, giving compounds of the following types ... 

Recently, Pattarawarapan and coworker reported the synthesis of a Si-supported DCT for scavenging nucleophiles [27]. 3-Aminopropyltrimethoxysilane was allowed to react with commercial silica gel in toluene. TCT (trichloroazine) was then reacted with the Si-immobilized amine to provide the supported DCT reagent. This was found to sequester both amines (primary and secondary) as well as alcohols with remarkable facility and two libraries of sulfonamides and amides were prepared in parallel format. Filtration was the sole purification step (Scheme 8.18). 

Class Ai. Compounds insoluble in water and in dilute sodium bicarbonate, but soluble in dilute sodium hydroxide solution. Weakly acidic compounds belong in this class. Weakly acidic properties are usually exhibited by oximes, imides, amino acids, sulfonamides of primary amines, primary and secondary nitro compounds, enols and phenols. Certain mercaptans also are weak acids. 

Alkylation of amines Primary and secondary amines can be alkylated by an... 

Reduction of carboxamides to amines. Primary and secondary amides are reduced by this complex hydride to amines in about 40-90y yield. Tertiary amides can be reduced by sodium trifluoroaeetoxyborohydride N-acetylindoline is converted into N-ethylindoIine in 64% yield. ... 

Oxidation of amines. Primary and secondary amines are oxidized, often in high yield, to imines, usually isolated as the corresponding carbonyl compound. The ix action is carried out in ethyl acetate at —78° under N2 (equation 1). 

Amines (primary and secondary) 7-Chloro-4-nitrobenzo-2-oxa-1,3-diazole (NBD-chloride) Formation of fluorescent derivatives... 

Copper (I) salts act as catalysts in the form of their complex with primary, secondary, or tertiary amines. Primary and secondary aliphatic amines must be used at low temperatures, since otherwise they are oxidized. Primary aromatic amines are oxidized to azo compounds, and secondary aromatic compounds probably to hydrazo compounds. Pyridine is very suitable. 

All epoxy compounds contain two or more of these groups. Epoxy resins may vary from low-viscosity liquids to high melting point solids. More than two dozen types are known. Tens of curing agents, including commonly available compounds such as amines, primary and secondary amines, and anhydrides are used. Only a few of these are used widely in adhesive formulations. ... 

Primary and Secondary Amines. Primary and secondary amines and their adducts are the most widely used curing agents for epoxy resins, accounting for close to 50% of all the epoxy curing agents used in the United States in 2001. 

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