Chem 503: Organic Chemistry II
Dr. Bryan Roberts
Aromatic Compounds
Ø The benzene ring possesses special stability because of cyclic delocalization of p electrons.
Ø Electrophilic aromatic substitution is one of the most important reactions of aromatic compounds because it leads to introduction of substituents on the benzene ring at predictable preferred positions.
Alcohols, Phenols, Ethers, and their Sulfur Analogues
Ø The physical properties of alcohols are dominated by their ability to serve as hydrogen bond donors and acceptors.
Ø Alcohols are important intermediates in organic synthesis and undergo a large number of reactions including dehydration and oxidation.
Ø The larger size of the sulfur atom influences the physical properties and chemistry of thiols, thiophenols, and thioethers.
Aldehydes and Ketones
Ø The polarity of the carbonyl group activates it toward reaction with Lewis acids and Lewis bases.
Ø Chemical tests can be used to distinguish compounds.
Ø Compounds that possess covalent metal-carbon bonds are the most important reagents for creating carbon-carbon bonds.
Enols and Enolates
Ø The reaction of enolates with electrophiles is one of the fundamentally important reactions for forming carbon-carbon bonds.
Ø The aldol condensation is an especially useful reaction for building up more complex carbon skeletons from simpler ones.
Carboxylic Acids and Derivatives
Ø Carboxylic acids and their derivatives are highly versatile organic compounds used widely in synthesis and commerce and participating in many important biochemical processes.
Ø The acidity of carboxylic acids depends upon structure.
Amines
Ø Amines include some of the most physiologically active compounds found in nature or made in the laboratory.
Ø The basicity of amines depends upon structure.
Ø Amines are good nucleophiles and participate in the SN2 reaction.
Ø Reaction of aniline or related aromatic amines with nitrous acid leads to a diazonium salt which is valuable in synthesis.
Ø The replacement of carbon atoms in aromatic compounds with nitrogen leads to heteroaromatic compounds.
Polymers
Ø Synthetic organic polymers permeate every aspect of our material life and are the foundation of our consumer-oriented society.
Ø There are two kinds of synthetic polymer: addition (chain-growth) polymers and condensation polymers.
Ø Specialized organometallic catalysts may be used to give polymers with regular stereochemistries.
Ø The physical properties of a polymer are a function of polymer structure.
Lipids
Ø Lipids constitute one of the major classes of naturally occurring organic compounds.
Ø Lipids include a diverse array of organic compounds including triglycerides, waxes, fatty acids, phospholipids, glycolipids, steroids, prostaglandins, leukotrienes, and terpenes.
Carbohydrates
Ø Carbohydrates constitute the most abundant class of naturally occurring organic compounds.
Ø In solution, monosaccharides exist as a mixture of the open chain form and cyclic forms.
Ø Monosaccharides combine through acetal linkages to give disaccharides and polysaccharides which perform many specialized functions in the chemistry of life.
Amino Acids, Peptides, and Proteins
Ø a-Amino acids are the building blocks of peptides and proteins.
Ø Peptides and proteins result from the combination of a-amino acids through amide linkages.
Ø Peptides and proteins perform many important functions in the chemistry of life including serving as catalysts, regulatory agents, structural material, and components of the immune system.
Ø A functioning peptide or protein adopts a specific three-dimensional shape which is determined by the geometry of the amide linkages and the interactions of the organic groups attached to the amino acid subunits.
Nucleic Acids
Ø Genetic information is encoded in the sequence of bases in the biopolymer deoxyribonucleic acid (DNA).
Ø DNA exists as a double helix in which complementary base pairs project toward the center of the helix and hydrogen bond with each other.
Ø In cell division, replication of the DNA results from separation of the double helix into template strands and construction of complementary strands on each of these.
Ø The genetic code is a three-letter code in which a sequence of three bases in DNA is transcribed into a sequence of three bases in ribonucleic acid (RNA) that is then translated into an amino acid subunit of a peptide or protein.
Ø A gene is a sequence of DNA which possess start and stop signals and which codes for a specific peptide or protein.
Ø In genetic engineering restriction enzymes are used to cut a gene from the DNA of one organism and to insert it into the DNA of another organism for the purpose of producing the peptide or protein coded for by the gene.