Chemistry 30: Organic Reactions and Biochemistry

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Chemistry 30 Organic Reactions and Biochemistry

• Christopher Chui

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Organic Reactions

• Substitution reactions a functional group
  replaces a hydrogen atom or another functional
  group
• Alcohols react with hydrogen halides to form
  alkyl halides
• Alkyl halides react with ammonia, NH3, to produce
  amines
• Addition reactions one bond of a double bond
  breaks to bond with some other atom
• Elimination reactions to remove certain atoms
  from a molecule to create a double bond HCl and
  HNO2 are often eliminated
• Esterification the reaction of an alcohol with
  an organic acid to produce an ester
• Saponification a metallic salt of the carboxylic
  acid is obtained, such as soap, which is a
  metallic salt of a fatty acid
• Polymerization compounds with double bonds add
  on to each other to form a polymer

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Petroleum

• Petroleum can be separated into portions with
  different boiling ranges by fractional
  distillation
• Crude oil can be used to manufacture hundreds of
  products gases, chemicals, gasoline, naphtha,
  kerosene, furnace oil, diesel oil, lubricating
  oil, asphalts, waxes, and coke
• Natural rubber is a polymer of 2-methylbutadiene
• A low-density organic polymer that conducts
  electricity better than copper is available in
  Germany
• Gasolines are rated by octane rating. High octane
• ?more ring compounds and highly-branched HC.
  Tetraethyl lead was used to improve octane rating

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Synthetic Rubber and Plastics

• Natural rubber is a polymer of 2-methylbutadiene
• Natural rubber and many synthetics are elastomers
• Plastics are made by polymerization
• Thousands of types of plastics polyethylene,
  polypropylene, polyvinyl chloride (PVC),
  polyvinyl acetate, polystyrene, Teflon, acrylics,
  etc
• Condensation polymerization produces polyesters
  and polyurethane
• Most polymers can be softened by heating, which
  can forced into molds to make thousands of
  products

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Synthetic Fibers

• Rayon is reconstituted cellulose
• Cellulose is a natural polymer of glucose,
  C6H12O6
• Nylon is the name for a group of polyamide fibers
• Nylon-66 can be made from adipic acid
  (hexanedioic acid) and hexamethylenediamine
  (1,6-diaminohexane). The amino group of the amine
  and the carboxyl group of the acid form an amide
  by condensation

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Proteins

• Proteins are polymers made of amino acids
• About ½ of proteins are enzymes
• Enzymes are catalysts to enable biochemical
  reactions at body temperatures
• Carboxylic acids react with amines to form amides
• Amide links are called peptide bonds
• Linking 2 amino acids is called a dipeptide
  linking 3 amino acids?tripeptide, etc
• A polypeptide with a biological function?protein
• Proteins differ in the order of amino acids, in
  the way the chain is folded, or twisted, and in
  the type of bonds holding the polymer in a
  particular shape

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Amino Acids

• Amino acids are not synthesized in the body
• Amino acids come from various food in the diet
• 20 left-handed amino acids are found in proteins
• Symbols of amino acids Gly, Ala, Val, Leu, Ile,
  Trp, Lys, Arg, Phe, His, Asn, Gln, Ser, Thr, Asp,
  Glu, Tyr, Met, Cys, Pro
• In cells, excess energy is used to produce ATP
• All organisms, from single-celled algae to
  humans, use ATP as their energy transfer molecule
• Crab shells (chitin) are used as pesticide to
  kill nematodes, which damage crops in the US

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Carbohydrates

• Carbohydrates are simple sugars or polymers of
  sugars, such as glucose, and fructose
• Combining two simple sugars produces a
  disaccharide
• Combining glucose and fructose?sucrose
• Plants store carbohydrates as starch
• Animals store carbohydrates as glycogen
• Glycogen, starch, and cellulose differ in the way
  the monomers are bonded to each other
• Carbohydrates break down in the organism to
  produce H2O, CO2, and energy

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Lipids (Fats)

• Proteins and carbohydrates are more soluble in
  H2O than in nonpolar solvents
• Lipids are more soluble in nonpolar solvents than
  in water
• Fats are esters formed from glycerol and fatty
  acids
• Fatty acids are carboxylic acids with 12 to 20 C
  atoms in the chain
• Animals fats are saturated and plant oils are not
• Steroids are lipids having a tetracyclic ring
  system
• Cholesterol is found in bile, and in cell
  membrane
• Some vitamins are lipids
• Vitamins are substances used by cells to aid
  enzymatic reactions
• Hemoglobin is the red pigment that is an oxygen
  carrier in humans and some other animals

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Nucleic Acids

• Nucleic acids are polymers of nucleotides
• Each nucleotide consists of a N-base, a sugar,
  and a phosphate group
• Only 2 sugars are found in nucleic acids ribose
  and deoxyribose
• 2 nucleic acids ribonucleic acid (RNA), and
  deoxyribonucleic acid (DNA)
• DNA consists of adenine, cytosine, guanine, and
  thymine RNA consists adenine, cytosine, guanine,
  uracil
• DNA is unique for each person DNA fingerprinting

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Biomaterials

• Biomedical engineering have continue to make
  replacement parts of the body artificial heart
  valves, ears, limbs, and organs
• Engineers have overcome the rejection problem
• Implanted biomaterials can cause blood clots
• Researchers are attempting to produce materials
  by imitating or reusing body materials
• Artificial blood vessels are usually made of
  Dacron or Teflon
• Pyrolytic carbon is a biomaterial, a
  noncrystalline form of carbon
• Biomolecular computing is the frontier of research