Chapter 1 Organic Chemistry

1. Chapter 1Organic Chemistry

2. Organic chemistry: the study of the compounds of carbon. • Organic compounds are made up of carbon and only a few other elements. • chief among these are hydrogen, oxygen, and nitrogen • also present are sulfur, phosphorus, and halogens (fluorine, chlorine, bromine, or iodine)

3. Why Carbon? • Why is organic chemistry a separate discipline within chemistry?

4. The sheer number of organic compounds • Chemists have discovered or made over 10 million organic compounds and an estimated 100,000 new ones are discovered or made each year. • By comparison, chemists have discovered or made an estimated 1.7 million inorganic compounds. • Thus, approximately 85% of all known compounds are organic.

5. The link to biochemistry • Carbohydrates, lipids, proteins, enzymes, nucleic acids, hormones, vitamins, and almost all other chemicals in living systems are organic compounds.

6. Historical: scientists at one time believed that a “vital force” present in living organisms was necessary to produce an organic compound. • The experiment of Wöhler in 1828 was the first in a series of experiments that led to the demise of the vital force theory.

9. Structure

10. Structural formula: shows the atoms present in a molecule as well as the bonds that connect them.

11. Lewis structure:A molecular representation that shows both the connections among atoms and the locations of lone-pair valence electrons.

12. Common bonding patterns for C, N, O, X, and H

13. VSEPR model: the most common bond angles are 109.5°, 120°, and 180°.

14. 3-D structure:Shows orientation in space, using wedges and dashes.

15. Condensed structure:Bonds are not specifically shown.

16. line-angle formula: • A line represents a carbon-carbon bond and a vertex and a line terminus represent a carbon atom. • Hydrogen atoms are not shown in line-angle formulas.

18. Constitutional isomers—compounds with the same molecular formula, but with different structural formulas (different connectivity).

19. For the molecular formula C4H10, two constitutional isomers are possible.

20. Functional Groups • Functional group: an atom or group of atoms within a molecule that shows a characteristic set of predictable physical and chemical properties.

22. Alcohol: contains an OH (hydroxyl) group bonded to a tetrahedral carbon atom. For example, ethanol:

24. Amine: a compound containing an amino group. • the amino group may be primary (1°), secondary (2°), or tertiary (3°).

26. Carbonyl group: C=O

27. Aldehyde: contains a carbonyl group bonded to a hydrogen; in formaldehyde, the simplest aldehyde, the carbonyl group is bonded to two hydrogens. • Ketone: contains a carbonyl group bonded to two carbon atoms.

29. Carboxylic acid: a compound containinga -COOH (carboxyl: carbonyl + hydroxyl) group. • In a condensed structural formula, a carboxyl group may also be written -CO2H.

31. Carboxylic ester: a derivative of a carboxylic acid in which the H of the carboxyl group is replaced by a carbon group.

33. Summary of Topics: Chapter 1 • What is Organic Chemistry? • Structural formulas • Lewis, condensed, line-angle • Constitutional isomers • Functional groups