CHEM 30 B Dr. R. Rinehart
Chapter 16: AMINES and AMIDES

Along with Chapter 15, this chapter will help to prepare us for our look at amino acids and proteins in Chapter 19. So this stuff is important!

I. AMINES: can be thought of as substituted ammonia molecules;
            A. Classification: by # of H in NH₃ replaced by R; NOTE differences from alcohol classes
                        1. Primary 1^o : RNH₂
                        2. Secondary 2^o : RNHR’ or R₂NH
                        3. Tertiary 3^o : RNR’R” or R₃N
            B. NOMENCLATURE
                        1. Common: Name the groups attached to N [in alphabetical order] followed by amine
                        2. IUPAC:
                                a. Use the prefix -amino with a number locant; to determine the longest
                                    relevant chain; the priority of the -NH₂ group is less than -OH but greater
                                    than C=O
                                 b. If the amino group is the highest priority group in the compound, locate
                                    the longest chain containing it and add the suffix –amine to the parent
                                    hydrocarbon name [minus the e at the end]; for secondary and tertiary
                                    amines, identify the other groups attached to nitrogen by name and prefix
                                    with N- to show that they are attached to the N
                        3. Aromatic amines: usually named as derivatives of aniline, C₆H₅NH₂

            C. Physical properties
                        1. b.p. higher than alkanes, less than alcohols of ~ m.w.
                        2. <C₆ soluble in H₂O
                        3. sharp, unpleasant, “fishy” odors [check out “putrescine” and “cadaverine”]

            D. Chemical properties and reactions:
                        1. Basicity: RNH₂ + H₂O à RNH₃⁺ + OH^-; Form salts with acids
                        2. Ammonium ions: 1^o RNH₃⁺, 2^o R₂NH₂⁺, 3^o R₃NH⁺ , 4^o R₄N⁺
                        3. React with carboxylic acids to form amides [an intermolecular dehydration]

            E . Biologically important amines and “alkaloids”
                        1. Hormones and neurotransmitters: (nor)epinephrine,dopamine, serotonin,
                                    histamine, etc.
                        2. Alkaloids: nitrogen-containing compounds from plants; many with
                                    pharmacological activity: opiates, cocaine, mescaline, caffeine, etc.

Click on links below to see my:
table of amines and N-containing heterocycles

table of amino acids

table of neurotransmitters, hormones, and alkaloids

To see Dave Woodcock's Chime structures of amines [new window] go to:
http://www.molecularmodels.ca/molecule/Amines.htm

PowerPoint-type presentation of nitrogen-containing functional groups [amines, amides, etc.] by Warren Gallagher at U Wisconsin Eau Claire is viewable [with Acrobat Reader] at:
http://web.archive.org/web/20060504011433/http://www.chem.uwec.edu/Chem150_S06/Pages/lecture-materials.html
> Lecture 4
http://www.chem.uwec.edu/Chem150_S06/Pages/lecture-materials.html > Lecture 4
Or, check http://www.chem.uwec.edu/Chem150_S07/content.html > Unit 7

Amines by Gary Trammell at the University of Illinois, Springfield
http://people.uis.edu/gtram1/organic/aminesmenu.htm

II. AMIDES: RCONH₂, RCONHR’, RCONR₂
            A. FORMATION from carboxylic acid [or anhydride] + NH₃, RNH₂, or R₂NH [NOT R₃N]
            B. NOMENCLATURE: based on the acid involved; e.g., N-methyl acetamide
            C. Physical properties: most are solids @ room temperature; <C₆ water-soluble
            D. CHEMICAL properties:
                        1. Neutral
                        2. Hydrolyzed by acid or base, but more stable than esters
                        3. The amide [“peptide”] bond is the basis of protein formation by the
                                    polymerization of a-amino acids
            E. Biologically and economically important amides
                        1. PROTEINS
                        2. drugs: acetaminophen, salicylamide, barbiturates, benzodiazepines [valium, etc.],
                                penicillins,etc.
                        3. polymers: nylon, Kevlar, Nomex, etc.

Click on link below to see my:
table of amides and polyamides

To see Dave Woodcock's Chime structures of amides [new window] go to:
http://www.molecularmodels.ca/molecule/Amides.htm