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Amine
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<h2 id="classification-of-amines">Classification of amines</h2> <p>Amines can be classified according to the nature and number of substituents on <a href="/facts/Nitrogen/Nf1QpGDz">nitrogen</a>. Aliphatic amines contain only H and alkyl substituents. <a href="/facts/Aromatic_amine/Az8ttGQT">Aromatic amines</a> have the nitrogen atom connected to an <a href="/facts/Aromaticity/wK0DzRY6">aromatic</a> ring. </p> <table><tbody><tr><th>Primary (1°) amine</th><th>Secondary (2°) amine</th><th>Tertiary (3°) amine</th></tr><tr><td></td><td></td><td></td></tr></tbody></table><p>Amines, alkyl and aryl alike, are organized into three subcategories (see table) based on the number of <a href="/facts/Carbon/ukrgQexo">carbon</a> atoms adjacent to the nitrogen (how many hydrogen atoms of the <a href="/facts/Ammonia/MtLtJFtz">ammonia</a> molecule are replaced by <a href="/facts/Hydrocarbon/Dcg95Ju5">hydrocarbon</a> groups):<a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a><a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a> </p><ul><li>Primary (1°) amines—Primary amines arise when one of three hydrogen atoms in <a href="/facts/Ammonia/MtLtJFtz">ammonia</a> is replaced by an <a href="/facts/Alkyl/vmEk8X4v">alkyl</a> or <a href="/facts/Aromatic/wK0DzRY6">aromatic</a> group. Important primary alkyl amines include <a href="/facts/Methylamine/srMMDp0D">methylamine</a>, most <a href="/facts/Amino_acid/WDxYwBny">amino acids</a>, and the <a href="/facts/Buffering_agent/zrLz9eaa">buffering agent</a> <a href="/facts/Tris/1nuYMVDA">tris</a>, while primary aromatic amines include <a href="/facts/Aniline/eFXck1Rj">aniline</a>.<a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a></li> <li>Secondary (2°) amines—Secondary amines have two organic substituents (alkyl, aryl or both) bound to the nitrogen together with one hydrogen. Important representatives include <a href="/facts/Dimethylamine/6ehYB5m0">dimethylamine</a>, while an example of an <a href="/facts/Aromatic_amine/Az8ttGQT">aromatic amine</a> would be <a href="/facts/Diphenylamine/CH92mQoC">diphenylamine</a>.<a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a></li> <li>Tertiary (3°) amines—In tertiary amines, nitrogen has three organic substituents. Examples include <a href="/facts/Trimethylamine/cj1dWmJq">trimethylamine</a>, which has a distinctively fishy smell, and <a href="/facts/EDTA/XvHgKQyD">EDTA</a>.<a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a></li></ul> <p>A fourth subcategory is determined by the connectivity of the substituents attached to the nitrogen: </p> <ul><li>Cyclic amines—<a href="/facts/Cyclic_compound/TH2ReKIQ">Cyclic</a> amines are either secondary or tertiary amines. Examples of cyclic amines include the 3-membered ring <a href="/facts/Aziridine/r89KuEYb">aziridine</a> and the six-membered ring <a href="/facts/Piperidine/dU6YTIC6">piperidine</a>. <i>N</i>-methylpiperidine and <i>N</i>-phenylpiperidine are examples of cyclic tertiary amines.<a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a></li></ul> <h3>Related compounds</h3> <p>Compounds where the <a href="/facts/Nitrogen/Nf1QpGDz">nitrogen</a> atom is attached to a <a href="/facts/Carbonyl_group/KJ71bo3X">carbonyl group</a>, thus having the structure R−C(=O)−NR′R″, are called <a href="/facts/Amide/C6kCzYEA">amides</a>. Compounds containing four organic substituents on the nitrogen, thus having the structure R4N+X−, are <a href="/facts/Quaternary_ammonium_salts/bNpF1goc">quaternary ammonium salts</a>. Many kinds of <a href="/facts/Anions/wrbwhF3z">anions</a> are found in such compounds. </p> <h2 id="naming-conventions">Naming conventions</h2> <p>Amines are named in several ways. Typically, the compound is given the prefix "amino-" or the suffix "-amine". The prefix "<i>N</i>-" shows substitution on the nitrogen atom. An organic compound with multiple amino groups is called a <a href="/facts/Diamine/y12h63fj">diamine</a>, <a href="/facts/Triamine/VntSgncL">triamine</a>, <a href="/facts/Tetraamine/VntSgncL">tetraamine</a> and so forth. </p><p>Lower amines are named with the suffix <i>-amine</i>. </p> <p>Higher amines have the prefix <i>amino</i> as a functional group. IUPAC however does not recommend this convention,<a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a> but prefers the alkanamine form, e.g. butan-2-amine. </p> <h2 id="physical-properties">Physical properties</h2> <p><a href="/facts/Hydrogen_bonding/85V86IIg">Hydrogen bonding</a> significantly influences the properties of primary and secondary amines. For example, <a href="/facts/Methylamine/srMMDp0D">methyl</a> and <a href="/facts/Ethylamine/Tj9X5ESb">ethyl</a> amines are gases under standard conditions, whereas the corresponding <a href="/facts/Methanol/EIfpoNCg">methyl</a> and <a href="/facts/Ethanol/3lCLfBSP">ethyl</a> alcohols are liquids. Amines possess a characteristic ammonia smell, liquid amines have a distinctive "fishy" and foul smell.<a class="footnote-ref" id="fnref:17" href="#fn:17"><sup>17</sup></a> </p><p>The nitrogen atom features a <a href="/facts/Lone_electron_pair/Q6kEAC4g">lone electron pair</a> that can bind H+ to form an <a href="/facts/Ammonium_ion/jYm8wc1n">ammonium ion</a> R3NH+. The lone electron pair is represented in this article by two dots above or next to the N. The water <a href="/facts/Solubility/kLE9h3Jb">solubility</a> of simple amines is enhanced by <a href="/facts/Hydrogen_bonding/85V86IIg">hydrogen bonding</a> involving these lone electron pairs. Typically salts of ammonium compounds exhibit the following order of solubility in water: primary ammonium (RNH+3) > secondary ammonium (R2NH+2) > tertiary ammonium (R3NH+). Small aliphatic amines display significant solubility in many <a href="/facts/Solvent/LoMPMz8S">solvents</a>, whereas those with large substituents are lipophilic. Aromatic amines, such as <a href="/facts/Aniline/eFXck1Rj">aniline</a>, have their lone pair electrons <a href="/facts/Conjugated_system/Ddx9qzox">conjugated</a> into the benzene ring, thus their tendency to engage in hydrogen bonding is diminished. Their boiling points are high and their solubility in water is low.<a class="footnote-ref" id="fnref:18" href="#fn:18"><sup>18</sup></a> </p> <h3>Spectroscopic identification</h3> <p>Typically the presence of an amine functional group is deduced by a combination of techniques, including mass spectrometry as well as NMR and IR spectroscopies. 1H NMR signals for amines disappear upon treatment of the sample with D2O. In their <a href="/facts/Infrared_spectrum/44XdJNcc">infrared spectrum</a> primary amines exhibit two N-H bands, whereas secondary amines exhibit only one.<a class="footnote-ref" id="fnref:19" href="#fn:19"><sup>19</sup></a> In their IR spectra, primary and secondary amines exhibit distinctive N-H stretching bands near 3300 cm−1. Somewhat less distinctive are the bands appearing below 1600 cm−1, which are weaker and overlap with C-C and C-H modes. For the case of <a href="/facts/Propyl_amine/4ufmcqfe">propyl amine</a>, the H-N-H scissor mode appears near 1600 cm−1, the C-N stretch near 1000 cm−1, and the R2N-H bend near 810 cm−1.<a class="footnote-ref" id="fnref:20" href="#fn:20"><sup>20</sup></a> </p> <h2 id="structure">Structure</h2> <h3>Alkyl amines</h3> <p>Alkyl amines characteristically feature tetrahedral nitrogen centers. C-N-C and C-N-H angles are near 109°. C-N distances are slightly shorter than C-C distances. The <a href="/facts/Activation_energy/GqkgPvo0">energy barrier</a> for the <a href="/facts/Nitrogen_inversion/soVo4lbf">nitrogen inversion</a> of the stereocenter is about 7 <a href="/facts/Kcal%2fmol/hBcdPkEY">kcal/mol</a> for a trialkylamine. The interconversion has been compared to the inversion of an open umbrella into a strong wind. </p><p>Amines of the type NHRR' and NRR′R″ are <a href="/facts/Chirality_(chemistry)/p5a9pftB">chiral</a>: the nitrogen center bears four substituents counting the lone pair. Because of the low barrier to inversion, amines of the type NHRR' cannot be obtained in optical purity. For chiral tertiary amines, NRR′R″ can only be resolved when the R, R', and R″ groups are constrained in cyclic structures such as <i>N</i>-substituted <a href="/facts/Aziridine/r89KuEYb">aziridines</a> (<a href="/facts/Quaternary_ammonium_salt/bNpF1goc">quaternary ammonium salts</a> are resolvable). </p> <h3>Aromatic amines</h3> <p>In aromatic amines ("anilines"), nitrogen is often nearly planar owing to conjugation of the lone pair with the aryl substituent. The C-N distance is correspondingly shorter. In aniline, the C-N distance is the same as the C-C distances.<a class="footnote-ref" id="fnref:21" href="#fn:21"><sup>21</sup></a> </p> <h2 id="basicity">Basicity</h2> <p>Like ammonia, amines are <a href="/facts/Base_(chemistry)/M9wA7qeM">bases</a>.<a class="footnote-ref" id="fnref:22" href="#fn:22"><sup>22</sup></a> Compared to alkali metal hydroxides, amines are weaker. </p> <table><tbody><tr><th>Alkylamine<a class="footnote-ref" id="fnref:23" href="#fn:23"><sup>23</sup></a> or aniline<a class="footnote-ref" id="fnref:24" href="#fn:24"><sup>24</sup></a></th><th>pKa of protonated amine</th><th><i>K</i>b</th></tr><tr><td><a href="/facts/Methylamine/srMMDp0D">Methylamine</a> (MeNH2)</td><td>10.62</td><td>4.17×10−4</td></tr><tr><td><a href="/facts/Dimethylamine/6ehYB5m0">Dimethylamine</a> (Me2NH)</td><td>10.64</td><td>4.37×10−4</td></tr><tr><td><a href="/facts/Trimethylamine/cj1dWmJq">Trimethylamine</a> (Me3N)</td><td> 9.76</td><td>5.75×10−5</td></tr><tr><td><a href="/facts/Ethylamine/Tj9X5ESb">Ethylamine</a> (EtNH2)</td><td>10.63</td><td>4.27×10−4</td></tr><tr><td><a href="/facts/Aniline/eFXck1Rj">Aniline</a> (PhNH2)</td><td> 4.62</td><td>4.17×10−10</td></tr><tr><td><a href="/facts/P-Anisidine/PSJ8LRbS">4-Methoxyaniline</a> (4-MeOC6H4NH2)</td><td> 5.36</td><td>2.29×10−9</td></tr><tr><td><a href="/facts/Dimethylaniline/G75Y4YST"><i>N</i>,<i>N</i>-Dimethylaniline</a> (PhNMe2)</td><td> 5.07</td><td>1.17×10−9</td></tr><tr><td><a href="/facts/3-Nitroaniline/kN1aGJHX">3-Nitroaniline</a> (3-NO2-C6H4NH2)</td><td> 2.46</td><td>2.88×10−12</td></tr><tr><td><a href="/facts/4-Nitroaniline/hD1dcV1y">4-Nitroaniline</a> (4-NO2-C6H4NH2)</td><td> 1.00</td><td>1.00×10−13</td></tr><tr><td>4-Trifluoromethylaniline (CF3C6H4NH2)</td><td> 2.75</td><td>5.62×10−12</td></tr></tbody></table> <p>The basicity of amines depends on: </p> <ol><li>The electronic properties of the substituents (alkyl groups enhance the basicity, aryl groups diminish it).</li> <li>The degree of solvation of the protonated amine, which includes <a href="/facts/Steric_hindrance/TnX5c8HG">steric hindrance</a> by the groups on nitrogen.</li></ol> <h3>Electronic effects</h3> <p>Owing to inductive effects, the basicity of an amine might be expected to increase with the number of alkyl groups on the amine. Correlations are complicated owing to the effects of solvation which are opposite the trends for inductive effects. Solvation effects also dominate the basicity of aromatic amines (anilines). For anilines, the lone pair of electrons on nitrogen delocalizes into the ring, resulting in decreased basicity. Substituents on the aromatic ring, and their positions relative to the amino group, also affect basicity as seen in the table. </p> <h3>Solvation effects</h3> <p>Solvation significantly affects the basicity of amines. N-H groups strongly interact with water, especially in ammonium ions. Consequently, the basicity of ammonia is enhanced by 1011 by solvation. The intrinsic basicity of amines, i.e. the situation where solvation is unimportant, has been evaluated in the gas phase. In the gas phase, amines exhibit the basicities predicted from the electron-releasing effects of the organic substituents. Thus tertiary amines are more basic than secondary amines, which are more basic than primary amines, and finally ammonia is least basic. The order of pKb's (basicities in water) does not follow this order. Similarly aniline is more basic than ammonia in the gas phase, but ten thousand times less so in aqueous solution.<a class="footnote-ref" id="fnref:25" href="#fn:25"><sup>25</sup></a> </p><p>In aprotic polar solvents such as <a href="/facts/Dimethyl_sulfoxide/T4HSYfuC">DMSO</a>, <a href="/facts/Dimethylformamide/wjI8UfB4">DMF</a>, and <a href="/facts/Acetonitrile/fNpbvRp6">acetonitrile</a> the energy of solvation is not as high as in protic polar solvents like water and methanol. For this reason, the basicity of amines in these aprotic solvents is almost solely governed by the electronic effects. </p> <h2 id="synthesis">Synthesis</h2> <h3>From alcohols</h3> <p>Industrially significant alkyl amines are prepared from ammonia by <a href="/facts/Alkylation/1rd5SNbt">alkylation</a> with alcohols:<a class="footnote-ref" id="fnref:26" href="#fn:26"><sup>26</sup></a> </p> ROH + NH 3 ⟶ RNH 2 + H 2 O {\displaystyle {\ce {ROH + NH3 -> RNH2 + H2O}}} <h3>From alkyl and aryl halides</h3> <p>Unlike the reaction of amines with alcohols the reaction of amines and ammonia with alkyl halides is used for synthesis in the laboratory: </p> RX + 2 R ′ NH 2 ⟶ RR ′ NH + [ RR ′ NH 2 ] X {\displaystyle {\ce {RX + 2 R'NH2 -> RR'NH + [RR'NH2]X}}} <p>In such reactions, which are more useful for alkyl iodides and bromides, the degree of alkylation is difficult to control such that one obtains mixtures of primary, secondary, and tertiary amines, as well as quaternary ammonium salts.<a class="footnote-ref" id="fnref:27" href="#fn:27"><sup>27</sup></a> </p><p>Selectivity can be improved via the <a href="/facts/Del%25C3%25A9pine_reaction/7bbr0NCM">Delépine reaction</a>, although this is rarely employed on an industrial scale. Selectivity is also assured in the <a href="/facts/Gabriel_synthesis/vYN14AFG">Gabriel synthesis</a>, which involves <a href="/facts/Organohalide/FTmWVdPT">organohalide</a> reacting with <a href="/facts/Potassium_phthalimide/FD4NIKjq">potassium phthalimide</a>. </p><p>Aryl halides are much less reactive toward amines and for that reason are more controllable. A popular way to prepare aryl amines is the <a href="/facts/Buchwald-Hartwig_reaction/va3ggoFB">Buchwald-Hartwig reaction</a>. </p> <h3>From alkenes</h3> <p>Disubstituted alkenes react with HCN in the presence of strong acids to give formamides, which can be decarbonylated. This method, the <a href="/facts/Ritter_reaction/QTBbpNSl">Ritter reaction</a>, is used industrially to produce tertiary amines such as tert-octylamine.<a class="footnote-ref" id="fnref:28" href="#fn:28"><sup>28</sup></a> </p><p>Hydroamination of alkenes is also widely practiced. The reaction is catalyzed by zeolite-based <a href="/facts/Solid_acid/ILa9AII5">solid acids</a>.<a class="footnote-ref" id="fnref:29" href="#fn:29"><sup>29</sup></a> </p> <h3>Reductive routes</h3> <p>Via the process of <a href="/facts/Hydrogenation/l7EzNSA7">hydrogenation</a>, unsaturated N-containing functional groups are reduced to amines using hydrogen in the presence of a nickel catalyst. Suitable groups include <a href="/facts/Nitrile/Gz7RCnC6">nitriles</a>, <a href="/facts/Organic_azide/FwdU5RM0">azides</a>, <a href="/facts/Imine/yK72z07j">imines</a> including <a href="/facts/Oxime/xRlPfB6K">oximes</a>, amides, and <a href="/facts/Nitro_compound/pem2BhMY">nitro</a>. In the case of nitriles, reactions are sensitive to acidic or alkaline conditions, which can cause hydrolysis of the −CN group. <a href="/facts/Lithium_aluminium_hydride/QMMhdqEy">LiAlH4</a> is more commonly employed for the reduction of these same groups on the laboratory scale. </p><p>Many amines are produced from aldehydes and ketones via <a href="/facts/Reductive_amination/U6duvSnx">reductive amination</a>, which can either proceed catalytically or stoichiometrically. </p><p><a href="/facts/Aniline/eFXck1Rj">Aniline</a> (C6H5NH2) and its derivatives are prepared by reduction of the nitroaromatics. In industry, hydrogen is the preferred reductant, whereas, in the laboratory, tin and iron are often employed. </p> <h3>Specialized methods</h3> <p>Many methods exist for the preparation of amines, many of these methods being rather specialized. </p> <table><tbody><tr><th>Reaction name</th><th>Substrate</th><th>Comment</th></tr><tr><td><a href="/facts/Staudinger_reduction/s63Hyq9D">Staudinger reduction</a></td><td><a href="/facts/Organic_azide/FwdU5RM0">Organic azide</a></td><td>This reaction also takes place with a reducing agent such as <a href="/facts/Lithium_aluminium_hydride/QMMhdqEy">lithium aluminium hydride</a>.</td></tr><tr><td><a href="/facts/Schmidt_reaction/zLcvTQCk">Schmidt reaction</a></td><td><a href="/facts/Carboxylic_acid/U4xuMosy">Carboxylic acid</a></td><td></td></tr><tr><td><a href="/facts/Aza-Baylis%25E2%2580%2593Hillman_reaction/E3nlCayk">Aza-Baylis–Hillman reaction</a></td><td><a href="/facts/Imine/yK72z07j">Imine</a></td><td>Synthesis of allylic amines</td></tr><tr><td><a href="/facts/Birch_reduction/0VPY857Y">Birch reduction</a></td><td><a href="/facts/Imine/yK72z07j">Imine</a></td><td>Useful for reactions that trap unstable imine intermediates, such as <a href="/facts/Grignard_reaction/DfhXQ6SG">Grignard reactions</a> with <a href="/facts/Nitrile/Gz7RCnC6">nitriles</a>.<a class="footnote-ref" id="fnref:30" href="#fn:30"><sup>30</sup></a></td></tr><tr><td><a href="/facts/Hofmann_rearrangement/ScW4RDIc">Hofmann degradation</a></td><td><a href="/facts/Amide/C6kCzYEA">Amide</a></td><td>This reaction is valid for preparation of primary amines only. Gives good yields of primary amines uncontaminated with other amines.</td></tr><tr><td><a href="/facts/Hofmann_elimination/yPhnFkXK">Hofmann elimination</a></td><td><a href="/facts/Quaternary_ammonium_salt/bNpF1goc">Quaternary ammonium salt</a></td><td>Upon treatment with strong base</td></tr><tr><td><a href="/facts/Leuckart_reaction/B7CfRx6H">Leuckart reaction</a></td><td><a href="/facts/Ketone/BqQXpLo4">Ketones</a> and <a href="/facts/Aldehyde/xSIRkW03">aldehydes</a></td><td><a href="/facts/Reductive_amination/U6duvSnx">Reductive amination</a> with <a href="/facts/Formic_acid/o6cFsbNc">formic acid</a> and <a href="/facts/Ammonia/MtLtJFtz">ammonia</a> via an <a href="/facts/Imine/yK72z07j">imine</a> intermediate</td></tr><tr><td><a href="/facts/Hofmann%25E2%2580%2593L%25C3%25B6ffler_reaction/VqwkHKG3">Hofmann–Löffler reaction</a></td><td>Haloamine</td><td></td></tr><tr><td><a href="/facts/Eschweiler%25E2%2580%2593Clarke_reaction/nECJjadu">Eschweiler–Clarke reaction</a></td><td>Amine</td><td><a href="/facts/Reductive_amination/U6duvSnx">Reductive amination</a> with <a href="/facts/Formic_acid/o6cFsbNc">formic acid</a> and <a href="/facts/Formaldehyde/Ck8RLfqk">formaldehyde</a> via an <a href="/facts/Imine/yK72z07j">imine</a> intermediate</td></tr></tbody></table> <h2 id="reactions">Reactions</h2> <h3>Alkylation, acylation, and sulfonation, etc.</h3> <p>Aside from their basicity, the dominant reactivity of amines is their <a href="/facts/Nucleophilicity/xYccoaJQ">nucleophilicity</a>.<a class="footnote-ref" id="fnref:31" href="#fn:31"><sup>31</sup></a> Most primary amines are good <a href="/facts/Ligand/6etB3qeW">ligands</a> for metal ions to give <a href="/facts/Coordination_complex/1tCyeQUm">coordination complexes</a>. Amines are alkylated by alkyl halides. <a href="/facts/Acyl_chloride/R4ppUXre">Acyl chlorides</a> and <a href="/facts/Organic_acid_anhydride/9YnWCsJo">acid anhydrides</a> react with primary and secondary amines to form <a href="/facts/Amide/C6kCzYEA">amides</a> (the "<a href="/facts/Schotten%25E2%2580%2593Baumann_reaction/IbajfjcL">Schotten–Baumann reaction</a>"). </p> <p>Similarly, with sulfonyl chlorides, one obtains <a href="/facts/Sulfonamide/h1sVXW41">sulfonamides</a>. This transformation, known as the <a href="/facts/Hinsberg_reaction/uKstRawS">Hinsberg reaction</a>, is a chemical test for the presence of amines. </p><p>Because amines are basic, they neutralize <a href="/facts/Acid/FySU18n1">acids</a> to form the corresponding <a href="/facts/Ammonium_salt/jYm8wc1n">ammonium salts</a> R3NH+. When formed from carboxylic acids and primary and secondary amines, these salts thermally dehydrate to form the corresponding <a href="/facts/Amide/C6kCzYEA">amides</a>. </p> H − N | R 2 R 1 | : ⏟ amine + R 3 − C O ‖ − OH ⏟ carboxylic acid − > H − N + | R 2 R 1 | − H + R 3 − COO − ⏟ substituted-ammonium carboxylate salt → dehydration heat N | R 2 R 1 | − C O ‖ − R 3 ⏟ amide + H 2 O ⏟ water {\displaystyle {\underbrace {\ce {H-\!\!{\overset {\displaystyle R1 \atop |}{\underset {| \atop \displaystyle R2}{N}}}\!\!\!\!:}} _{\text{amine}}+\underbrace {\ce {R3-{\overset {\displaystyle O \atop \|}{C}}-OH}} _{\text{carboxylic acid}}->}\ \underbrace {\ce {{H-{\overset {\displaystyle R1 \atop |}{\underset {| \atop \displaystyle R2}{N+}}}-H}+R3-COO^{-}}} _{{\text{substituted-ammonium}} \atop {\text{carboxylate salt}}}{\ce {->[{\text{heat}}][{\text{dehydration}}]}}{\underbrace {\ce {{\overset {\displaystyle R1 \atop |}{\underset {| \atop \displaystyle R2}{N}}}\!\!-{\overset {\displaystyle O \atop \|}{C}}-R3}} _{\text{amide}}+\underbrace {\ce {H2O}} _{\text{water}}}} <p>Amines undergo <a href="/facts/Sulfamation/52A0SkvA">sulfamation</a> upon treatment with <a href="/facts/Sulfur_trioxide/Ijvm08Lq">sulfur trioxide</a> or sources thereof: </p> R 2 NH + SO 3 ⟶ R 2 NSO 3 H {\displaystyle {\ce {R2NH + SO3 -> R2NSO3H}}} <h3>Diazotization</h3> <p>Amines reacts with <a href="/facts/Nitrous_acid/xaVd1w2D">nitrous acid</a> to give diazonium salts. The alkyl diazonium salts are of little importance because they are too unstable. The most important members are derivatives of aromatic amines such as <a href="/facts/Aniline/eFXck1Rj">aniline</a> ("phenylamine") (A = aryl or naphthyl): </p> ANH 2 + HNO 2 + HX ⟶ AN 2 + + X − + 2 H 2 O {\displaystyle {\ce {ANH2 + HNO2 + HX -> AN2+ + X- + 2 H2O}}} <p>Anilines and naphthylamines form more stable <a href="/facts/Diazonium/5pkN4G5s">diazonium</a> salts, which can be isolated in the crystalline form.<a class="footnote-ref" id="fnref:32" href="#fn:32"><sup>32</sup></a> Diazonium salts undergo a variety of useful transformations involving replacement of the N2 group with anions. For example, <a href="/facts/Copper(I)_cyanide/sgg8KgRw">cuprous cyanide</a> gives the corresponding nitriles: </p> AN 2 + + Y − ⟶ AY + N 2 {\displaystyle {\ce {AN2+ + Y- -> AY + N2}}} <p>Aryldiazoniums couple with electron-rich aromatic compounds such as a <a href="/facts/Phenol/ACJs5NIU">phenol</a> to form <a href="/facts/Azo_compound/dnl1WKnK">azo compounds</a>. Such reactions are widely applied to the production of dyes.<a class="footnote-ref" id="fnref:33" href="#fn:33"><sup>33</sup></a> </p> <h3>Conversion to imines</h3> <p><a href="/facts/Alkylimino-de-oxo-bisubstitution/d4XahHwm">Imine formation</a> is an important reaction. Primary amines react with <a href="/facts/Ketone/BqQXpLo4">ketones</a> and <a href="/facts/Aldehyde/xSIRkW03">aldehydes</a> to form <a href="/facts/Imine/yK72z07j">imines</a>. In the case of <a href="/facts/Formaldehyde/Ck8RLfqk">formaldehyde</a> (R' = H), these products typically exist as cyclic <a href="/facts/Trimer_(chemistry)/ws3JkjuQ">trimers</a>: RNH 2 + R 2 ′ C = O ⟶ R 2 ′ C = NR + H 2 O {\displaystyle {\ce {RNH2 + R'_2C=O -> R'_2C=NR + H2O}}} Reduction of these imines gives secondary amines: R 2 ′ C = NR + H 2 ⟶ R 2 ′ CH − NHR {\displaystyle {\ce {R'_2C=NR + H2 -> R'_2CH-NHR}}} </p><p>Similarly, secondary amines react with ketones and aldehydes to form <a href="/facts/Enamine/TaubsvCU">enamines</a>: R 2 NH + R ′ ( R ″ CH 2 ) C = O ⟶ R ″ CH = C ( NR 2 ) R ′ + H 2 O {\displaystyle {\ce {R2NH + R'(R''CH2)C=O -> R''CH=C(NR2)R' + H2O}}} </p><p><a href="/facts/Mercuric/WlxfoHva">Mercuric</a> ions reversibly oxidize <a href="/facts/Tertiary_amine/SN7W44fv">tertiary amines</a> with an <a href="/facts/Locant/HwU4BBRY">α</a> hydrogen to <a href="/facts/Iminium/eLFxYGI3">iminium</a> ions:<a class="footnote-ref" id="fnref:34" href="#fn:34"><sup>34</sup></a> Hg 2 + + R 2 NCH 2 R ′ ↽ − − ⇀ Hg + [ R 2 N = CHR ′ ] + + H + {\displaystyle {\ce {Hg^2+ + R2NCH2R' <=> Hg + [R2N=CHR']+ + H+}}} </p> <h3>Overview</h3> <p>An overview of the reactions of amines is given below: </p> <table><tbody><tr><th>Reaction name</th><th>Reaction product</th><th>Comment</th></tr><tr><td><a href="/facts/Amine_alkylation/DvhmtUEY">Amine alkylation</a></td><td>Amines</td><td>Degree of substitution increases</td></tr><tr><td><a href="/facts/Schotten%25E2%2580%2593Baumann_reaction/IbajfjcL">Schotten–Baumann reaction</a></td><td><a href="/facts/Amide/C6kCzYEA">Amide</a></td><td>Reagents: <a href="/facts/Acyl_chloride/R4ppUXre">acyl chlorides</a>, <a href="/facts/Acid_anhydride/0LvHIgAY">acid anhydrides</a></td></tr><tr><td><a href="/facts/Hinsberg_reaction/uKstRawS">Hinsberg reaction</a></td><td><a href="/facts/Sulfonamide/h1sVXW41">Sulfonamides</a></td><td>Reagents: <a href="/facts/Sulfonyl_chloride/rIxWBYf3">sulfonyl chlorides</a></td></tr><tr><td><a href="/facts/Amine-carbonyl_condensation/d4XahHwm">Amine–carbonyl condensation</a></td><td><a href="/facts/Imines/yK72z07j">Imines</a></td></tr><tr><td><a href="/facts/Organic_oxidation/6DdmXG4S">Organic oxidation</a></td><td><a href="/facts/Nitroso/Irref1C6">Nitroso</a> compounds</td><td>Reagent: <a href="/facts/Peroxymonosulfuric_acid/kI1oC4JL">peroxymonosulfuric acid</a></td></tr><tr><td><a href="/facts/Organic_oxidation/6DdmXG4S">Organic oxidation</a></td><td><a href="/facts/Diazonium_salt/5pkN4G5s">Diazonium salt</a></td><td>Reagent: <a href="/facts/Nitrous_acid/xaVd1w2D">nitrous acid</a></td></tr><tr><td><a href="/facts/Zincke_reaction/mJfXhQRz">Zincke reaction</a></td><td><a href="/facts/Zincke_aldehyde/o0yhszdb">Zincke aldehyde</a></td><td>Reagent: <a href="/facts/Pyridinium/txxbe0vf">pyridinium</a> salts, with primary and secondary amines</td></tr><tr><td><a href="/facts/Emde_degradation/2sXEvKhp">Emde degradation</a></td><td><a href="/facts/Tertiary_amine/SN7W44fv">Tertiary amine</a></td><td>Reduction of <a href="/facts/Quaternary_ammonium_cation/bNpF1goc">quaternary ammonium cations</a></td></tr><tr><td><a href="/facts/Hofmann%25E2%2580%2593Martius_rearrangement/5XmAoyAq">Hofmann–Martius rearrangement</a></td><td>Aryl-substituted <a href="/facts/Aniline/eFXck1Rj">anilines</a></td></tr><tr><td><a href="/facts/Von_Braun_reaction/xXAaPzAR">von Braun reaction</a></td><td><a href="/facts/Nitrile/Gz7RCnC6">Organic cyanamide</a></td><td>By cleavage (tertiary amines only) with cyanogen bromide</td></tr><tr><td><a href="/facts/Hofmann_elimination/yPhnFkXK">Hofmann elimination</a></td><td><a href="/facts/Alkene/RtYcS6kU">Alkene</a></td><td>Proceeds by β-elimination of less hindered carbon</td></tr><tr><td><a href="/facts/Cope_reaction/hlkvGWUm">Cope reaction</a></td><td><a href="/facts/Alkene/RtYcS6kU">Alkene</a></td><td>Similar to <a href="/facts/Hofmann_elimination/yPhnFkXK">Hofmann elimination</a></td></tr><tr><td><a href="/facts/Carbylamine_reaction/gQlxegEF">Carbylamine reaction</a></td><td><a href="/facts/Isonitrile/VmkIBMKR">Isonitrile</a></td><td>Primary amines only</td></tr><tr><td>Hofmann's mustard oil test</td><td><a href="/facts/Isothiocyanate/zk3Q3Pv8">Isothiocyanate</a></td><td><a href="/facts/Carbon_disulfide/b04Tadmy">Carbon disulfide</a> CS2 and <a href="/facts/Mercury(II)_chloride/aUAKsq6a">mercury(II) chloride</a> HgCl2 are used. Thiocyanate smells like mustard.</td></tr></tbody></table> <h2 id="biological-activity">Biological activity</h2> <p>Amines are ubiquitous in biology. The breakdown of <a href="/facts/Amino_acid/WDxYwBny">amino acids</a> releases amines, famously in the case of decaying fish which smell of <a href="/facts/Trimethylamine/cj1dWmJq">trimethylamine</a>. Many <a href="/facts/Neurotransmitter/LlpYFSU3">neurotransmitters</a> are amines, including <a href="/facts/Epinephrine/k7vvMI7E">epinephrine</a>, <a href="/facts/Norepinephrine/AjTIC9ox">norepinephrine</a>, <a href="/facts/Dopamine/5gNy8Xkd">dopamine</a>, <a href="/facts/Serotonin/EzY58q4a">serotonin</a>, and <a href="/facts/Histamine/Vfjda665">histamine</a>. <a href="/facts/Protonated/q5Gf9z0M">Protonated</a> <a href="/facts/Amino_group/SN7W44fv">amino groups</a> (–NH+3) are the most common positively charged moieties in <a href="/facts/Protein/Jxmagu3E">proteins</a>, specifically in the amino acid <a href="/facts/Lysine/CEetgA9L">lysine</a>.<a class="footnote-ref" id="fnref:35" href="#fn:35"><sup>35</sup></a> The anionic polymer <a href="/facts/DNA/nB89Iauz">DNA</a> is typically bound to various amine-rich proteins.<a class="footnote-ref" id="fnref:36" href="#fn:36"><sup>36</sup></a> Additionally, the terminal charged primary ammonium on lysine forms <a href="/facts/Salt_bridge_(protein_and_supramolecular)/cjEeeG9v">salt bridges</a> with <a href="/facts/Carboxylate/vEDekXRr">carboxylate</a> groups of other amino acids in <a href="/facts/Polypeptide/C4ltc7UG">polypeptides</a>, which is one of the primary influences on the three-dimensional structures of proteins.<a class="footnote-ref" id="fnref:37" href="#fn:37"><sup>37</sup></a> </p> <h3>Amine hormones</h3> <p><a href="/facts/Hormone/WFnBnINJ">Hormones</a> derived from the modification of amino acids are referred to as amine hormones. Typically, the original structure of the amino acid is modified such that a –COOH, or carboxyl, group is removed, whereas the –NH+3, or amine, group remains. Amine hormones are synthesized from the amino acids <a href="/facts/Tryptophan/JcUxlxAh">tryptophan</a> or <a href="/facts/Tyrosine/RJhEgE4C">tyrosine</a>.<a class="footnote-ref" id="fnref:38" href="#fn:38"><sup>38</sup></a> </p> <h2 id="application-of-amines">Application of amines</h2> <h3>Dyes</h3> <p>Primary aromatic amines are used as a starting material for the manufacture of <a href="/facts/Azo_dye/5zBT0p8G">azo dyes</a>. It reacts with nitrous acid to form diazonium salt, which can undergo coupling reaction to form an azo compound. As azo-compounds are highly coloured, they are widely used in dyeing industries, such as: </p> <ul><li><a href="/facts/Methyl_orange/GQLXo1Pl">Methyl orange</a></li> <li>Direct brown 138</li> <li><a href="/facts/Sunset_yellow/xNUYqYM0">Sunset yellow</a> FCF</li> <li><a href="/facts/Ponceau_4R/voQ6yDR9">Ponceau</a></li></ul> <h3>Drugs</h3> <p>Most drugs and drug candidates contain amine functional groups:<a class="footnote-ref" id="fnref:39" href="#fn:39"><sup>39</sup></a> </p> <ul><li><a href="/facts/Chlorpheniramine/fuBFmrko">Chlorpheniramine</a> is an <a href="/facts/Antihistamine/HuMC25lt">antihistamine</a> that helps to relieve allergic disorders due to cold, hay fever, itchy skin, insect bites and stings.</li> <li><a href="/facts/Chlorpromazine/oFja1FYA">Chlorpromazine</a> is a tranquilizer that sedates without inducing sleep. It is used to relieve anxiety, excitement, restlessness or even mental disorder.</li> <li><a href="/facts/Ephedrine/wxXefYXQ">Ephedrine</a> and <a href="/facts/Phenylephrine/sf4DxQws">phenylephrine</a>, as amine hydrochlorides, are used as decongestants.</li> <li><a href="/facts/Amphetamine/yKIpLJ9E">Amphetamine</a>, <a href="/facts/Methamphetamine/vS1jloMe">methamphetamine</a>, and <a href="/facts/Methcathinone/tF4VcbcI">methcathinone</a> are psychostimulant amines that are listed as controlled substances by the US <a href="/facts/Drug_Enforcement_Administration/qGQpHNB8">DEA</a>.</li> <li><a href="/facts/Thioridazine/um69HuvU">Thioridazine</a>, an antipsychotic drug, is an amine which is believed to exhibit its antipsychotic effects, in part, due to its effects on other amines.<a class="footnote-ref" id="fnref:40" href="#fn:40"><sup>40</sup></a></li> <li><a href="/facts/Amitriptyline/7YGkJGfr">Amitriptyline</a>, <a href="/facts/Imipramine/3ppWvEKp">imipramine</a>, <a href="/facts/Lofepramine/JDHnFFL0">lofepramine</a> and <a href="/facts/Clomipramine/wnhL4NfS">clomipramine</a> are <a href="/facts/Tricyclic_antidepressant/vpBLER2Q">tricyclic antidepressants</a> and tertiary amines.</li> <li><a href="/facts/Nortriptyline/predd7gA">Nortriptyline</a>, <a href="/facts/Desipramine/1NvuPY6M">desipramine</a>, and <a href="/facts/Amoxapine/aUpJHYX4">amoxapine</a> are <a href="/facts/Tricyclic_antidepressants/vpBLER2Q">tricyclic antidepressants</a> and secondary amines. (The tricyclics are grouped by the nature of the final amino group on the side chain.)</li> <li><a href="/facts/Substituted_tryptamine/rNKEIl5T">Substituted tryptamines</a> and <a href="/facts/Substituted_phenethylamine/dte6TQxS">phenethylamines</a> are key basic structures for a large variety of <a href="/facts/Psychedelic_drug/aj9GNANW">psychedelic drugs</a>.</li> <li><a href="/facts/Opiate/IHfQkMkU">Opiate</a> <a href="/facts/Analgesic/xLj4XBcq">analgesics</a> such as <a href="/facts/Morphine/8ngpXHDc">morphine</a>, <a href="/facts/Codeine/lr7WHXmX">codeine</a>, and <a href="/facts/Heroin/rYwrKHPk">heroin</a> are <a href="/facts/Tertiary_(chemistry)/2tdmz8wG">tertiary</a> amines.</li></ul> <h3>Gas treatment</h3> <p>Aqueous <a href="/facts/Monoethanolamine/L8dIQuKf">monoethanolamine</a> (MEA), diglycolamine (DGA), <a href="/facts/Diethanolamine/Tu33IQqc">diethanolamine</a> (DEA), <a href="/facts/Diisopropanolamine/puRlQR7L">diisopropanolamine</a> (DIPA) and <a href="/facts/N-methyl-diethanolamine/TAtHek7j">methyldiethanolamine</a> (MDEA) are widely used industrially for removing <a href="/facts/Carbon_dioxide/xGzpppEp">carbon dioxide</a> (CO2) and <a href="/facts/Hydrogen_sulfide/UbCqjMMk">hydrogen sulfide</a> (H2S) from natural gas and refinery process streams. They may also be used to remove CO2 from combustion gases and <a href="/facts/Flue_gas/ETBGr9II">flue gases</a> and may have potential for abatement of <a href="/facts/Greenhouse_gas/HXaHqrT8">greenhouse gases</a>. Related processes are known as <a href="/facts/Amine_gas_treating/oJ0HHFQV">sweetening</a>.<a class="footnote-ref" id="fnref:41" href="#fn:41"><sup>41</sup></a> </p> <h3>Epoxy resin curing agents</h3> <p>Amines are often used as epoxy resin curing agents.<a class="footnote-ref" id="fnref:42" href="#fn:42"><sup>42</sup></a><a class="footnote-ref" id="fnref:43" href="#fn:43"><sup>43</sup></a> These include <a href="/facts/Dimethylethylamine/sYrIEXkQ">dimethylethylamine</a>, <a href="/facts/Cyclohexylamine/yCFsNUcf">cyclohexylamine</a>, and a variety of diamines such as 4,4-diaminodicyclohexylmethane.<a class="footnote-ref" id="fnref:44" href="#fn:44"><sup>44</sup></a> Multifunctional amines such as <a href="/facts/Tetraethylenepentamine/n7zkp0xG">tetraethylenepentamine</a> and <a href="/facts/Triethylenetetramine/VHwtF7DE">triethylenetetramine</a> are also widely used in this capacity.<a class="footnote-ref" id="fnref:45" href="#fn:45"><sup>45</sup></a> The reaction proceeds by the lone pair of electrons on the amine nitrogen attacking the outermost carbon on the oxirane ring of the epoxy resin. This relieves ring strain on the epoxide and is the driving force of the reaction.<a class="footnote-ref" id="fnref:46" href="#fn:46"><sup>46</sup></a> Molecules with tertiary amine functionality are often used to accelerate the epoxy-amine curing reaction and include substances such as <a href="/facts/2%2c4%2c6-Tris(dimethylaminomethyl)phenol/5Gq3U7TH">2,4,6-Tris(dimethylaminomethyl)phenol</a>. It has been stated that this is the most widely used room temperature accelerator for two-component epoxy resin systems.<a class="footnote-ref" id="fnref:47" href="#fn:47"><sup>47</sup></a><a class="footnote-ref" id="fnref:48" href="#fn:48"><sup>48</sup></a> </p> <h2 id="safety">Safety</h2> <p>Low molecular weight simple amines, such as <a href="/facts/Ethylamine/Tj9X5ESb">ethylamine</a>, are toxic with <a href="/facts/Median_lethal_dose/PSTer8Wv">LD50</a> between 100 and 1000 mg/kg. They are skin irritants, especially as some are easily absorbed through the skin.<a class="footnote-ref" id="fnref:49" href="#fn:49"><sup>49</sup></a> Amines are a broad class of compounds, and more complex members of the class can be extremely bioactive, for example <a href="/facts/Strychnine/oaAfW1xP">strychnine</a>. </p> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/Acid%25E2%2580%2593base_extraction/H0LGtLjj">Acid–base extraction</a></li> <li><a href="/facts/Amine_value/C6K7B9h7">Amine value</a></li> <li><a href="/facts/Amine_gas_treating/oJ0HHFQV">Amine gas treating</a></li> <li><a href="/facts/Ammine/xvd6F14I">Ammine</a></li> <li><a href="/facts/Biogenic_amine/2wGIhB2o">Biogenic amine</a></li> <li><a href="/facts/Ligand_isomerism/rzLYFYhs">Ligand isomerism</a></li> <li><a href="/facts/IUPAC_nomenclature_of_organic_chemistry/ElygYu14">Official naming rules for amines</a> as determined by the International Union of Pure and Applied Chemistry (<a href="/facts/IUPAC/2AV6myCK">IUPAC</a>)</li></ul> <h2 id="further-reading">Further reading</h2> <ul><li><a href="https://courses.lumenlearning.com/introchem/chapter/amines/#:~:text=The%20amine%20functional%20group%20contains,by%20a%20carbon-containing%20substituent.&text=Amine%20groups%20bonded%20to%20an,are%20known%20as%20aromatic%20amines.">"Amines | Introduction to Chemistry"</a>. <i>courses.lumenlearning.com</i>. Retrieved 22 July 2021.</li> <li>Flick, Ernest W. (1993). <a href="https://www.worldcat.org/oclc/915134542"><i>Epoxy Resins, Curing Agents, Compounds, and Modifiers: An Industrial Guide</i></a>. Park Ridge, NJ: Noyes Publications. <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 978-0-8155-1708-5. <a href="/facts/OCLC_(identifier)/Yqad8waq">OCLC</a> <a href="https://search.worldcat.org/oclc/915134542">915134542</a>.</li></ul> <h2 id="external-links">External links</h2> Wikiquote has quotations related to <i>Amine</i>. <ul><li><a href="https://www.organic-chemistry.org/synthesis/C1N/amines/primaryamines.shtm">Synthesis of amines</a></li> <li><a href="http://www.millhousemedical.co.nz/files/docs/factsheet_7_amines_in_foods.pdf">Factsheet, amines in food</a> <a href="https://web.archive.org/web/20180219074057/http://www.millhousemedical.co.nz/files/docs/factsheet_7_amines_in_foods.pdf">Archived</a> 19 February 2018 at the <a href="/facts/Wayback_Machine/nmQ3a6JC">Wayback Machine</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>"amine". The American Heritage Dictionary of the English Language (5th ed.). HarperCollins. <a href="https://www.ahdictionary.com/word/search.html?q=amine" target="_blank">https://www.ahdictionary.com/word/search.html?q=amine</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>"Amine definition and meaning". Collins English Dictionary. Archived from the original on 23 February 2015. Retrieved 28 March 2017. <a href="https://www.collinsdictionary.com/dictionary/english/amine" target="_blank">https://www.collinsdictionary.com/dictionary/english/amine</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>"amine – definition of amine in English". Oxford Dictionaries. Archived from the original on 23 February 2015. Retrieved 28 March 2017. <a href="https://web.archive.org/web/20150223133030/http://www.oxforddictionaries.com/us/definition/english/amine" target="_blank">https://web.archive.org/web/20150223133030/http://www.oxforddictionaries.com/us/definition/english/amine</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Anderson, Gregory; Fahey, Caryn; Richards, Adrienne; Sauer, Samantha Sullivan; Wegman, David; Booth, Jen (16 February 2024). "26.1 Amines – Structure and Naming". Open Library. <a href="https://ecampusontario.pressbooks.pub/orgbiochemsupplement/chapter/naming-amines/" target="_blank">https://ecampusontario.pressbooks.pub/orgbiochemsupplement/chapter/naming-amines/</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Bhuyan, Satyam (25 August 2023). "Amines: Definition, Structure, Type, and Example". Chemistry Learner. Retrieved 27 May 2025. <a href="https://www.chemistrylearner.com/amines.html" target="_blank">https://www.chemistrylearner.com/amines.html</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>PubChem. "Aniline". pubchem.ncbi.nlm.nih.gov. Retrieved 27 May 2025. <a href="https://pubchem.ncbi.nlm.nih.gov/compound/6115" target="_blank">https://pubchem.ncbi.nlm.nih.gov/compound/6115</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>Eller, Karsten; Henkes, Erhard; Rossbacher, Roland; Höke, Hartmut (2000). "Amines, Aliphatic". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a02_001. ISBN 3527306730. <a href="3527306730" target="_blank">3527306730</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>Lyons, Kate. "LibGuides: CHE 120 - Introduction to Organic Chemistry - Textbook: Chapter 5 - Amines and Amides". guides.hostos.cuny.edu. Retrieved 27 May 2025. <a href="https://guides.hostos.cuny.edu/che120/chapter5" target="_blank">https://guides.hostos.cuny.edu/che120/chapter5</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>Smith, Janice Gorzynski (2011). "Chapter 25 Amines". Organic chemistry (3rd ed.). New York, NY: McGraw-Hill. pp. 949–993. ISBN 978-0-07-337562-5. Archived from the original (Book) on 28 June 2018. Retrieved 26 June 2018. <a href="978-0-07-337562-5" target="_blank">978-0-07-337562-5</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>Smith, Janice Gorzynski (2011). "Chapter 25 Amines". Organic chemistry (3rd ed.). New York, NY: McGraw-Hill. pp. 949–993. ISBN 978-0-07-337562-5. Archived from the original (Book) on 28 June 2018. Retrieved 26 June 2018. <a href="978-0-07-337562-5" target="_blank">978-0-07-337562-5</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> <li id="fn:11"><p>Lawrence, Stephen A. (2004). Amines : synthesis, properties, and applications. New York: Cambridge University Press. ISBN 0521782848. <a href="0521782848" target="_blank">0521782848</a> <a href="#fnref:11" class="footnote-back-ref">↩</a></p></li> <li id="fn:12"><p>"3: Amines and Amides". Chemistry LibreTexts. 9 July 2020. Retrieved 27 May 2025. <a href="https://chem.libretexts.org/Courses/Brevard_College/CHE_202%3A_Organic_Chemistry_II/03%3A_Amines_and_Amides" target="_blank">https://chem.libretexts.org/Courses/Brevard_College/CHE_202%3A_Organic_Chemistry_II/03%3A_Amines_and_Amides</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></p></li> <li id="fn:13"><p>"3: Amines and Amides". Chemistry LibreTexts. 9 July 2020. 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