Organic Chemistry

1. Organic Chemistry The study of carbon-based compounds and their properties.

2. Organic Chemistry

3. Organic Chemistry

4. Organic Chemistry Historically the distinction between inorganic and organic substances was based on whether or not they were produced by living systems. It was believed that some sort of “life force” was needed to synthesize them.

5. however... NH4OCN  H2N—C—NH2 O urea In 1828, the German chemist Freidrich Wohler (1800-1882) prepared urea from the inorganic salt ammonium cyanate by simple heating.

6. Hydrocarbons: contain only hydrogen and carbon Hydrocarbons can be divided into different types, depending on their bonding. Hydrocarbons Aliphatic Aromatic Alkanes Alkenes Alkynes Cyclic

7. Naming Organic Molecules Alkanes - - Carbon chain, no double or triple bonds. All single bonds (saturated) Alkenes - - Carbon chain, contains double bond(s) (unsaturated) Alkynes - - Carbon chain, contains triple bond(s) (unsaturated)

8. Naming Organic Molecules There are two parts to the main name of each molecule… suffix: tells the type of bonding in the chain or ring prefix: tells the # of carbons in main chain or ring

9. Prefix: indicates number of carbon atoms in the main chain or ring • meth- • eth- • prop- • but- • pent- • 6 hex- • 7 hept- • oct- • non- • dec-

10. Suffix: indicates types of bonds present Alkanes: (all single bonds) ___ -ane Alkenes: (double bond) ___ -ene Alkyne: (triple bond) ___ -yne

11. Saturated Hydrocarbons: • the ALKANES: chains of carbon connected by single bonds: • contain only single C-C bonds

12. Saturated v. Unsaturated fats Saturated with H Single bonds are free to rotate, so these fats can pack tightly (solid @ room temp)

13. Which one is saturated?

14. For a bit of a demonstration… • Good Eats fat train analogy Watch episode from 1:30 to 5:00

15. ALKANES

16. ALKANES

17. ALKANESpropane, C3H8

18. ALKANESbutane, C4H10

19. ALKANESpentane, C5H12

20. ALKANEShexane, C6H14

21. ALKANESoctane, C8H18

22. Don’t write this example down, but watch to see where we’re going with this…

23. (Although you will be required to include the H’s if you take IB Chemistry)

26. “Normal” v. Branched • “normal” hydrocarbons are straight chains; no branching • Branched-chain hydrocarbons – isomers of “normal” hydrocarbons; have same formula, but different structures

27. n-butane

28. 2-methlypropane

29. n-pentane

30. 2-methylbutane

31. Are there any other pentane isomers?

32. Another branched alkane: 2,2-dimethylpentane

33. cyclopentane Cycloalkanes

34. Cycloalkanes • cyclobutane

35. Cycloalkanes -ethyl- -methylcyclopentane 1 3 • ________________________ methyl- 3 1 green or red? 2 2 3 1 ethyl-

36. Unsaturated Hydrocarbons: ALKENES – contain C-C double bonds2-pentene

37. Unsaturated Hydrocarbons: ALKENES – contain C-C double bonds2,4-hexadiene

38. Unsaturated Hydrocarbons: ALKYNES – contain C-C triple bonds1-butyne

39. Unsaturated Hydrocarbons: ALKYNES – contain C-C triple bonds3-ethyl-1-pentyne

40. Aromatic Hydrocarbons: benzene – the simplest aromatic hydrocarbon; has a symmetrical ring structure

41. Aromatic Hydrocarbons: benzene – can be drawn like this…

42. Derivatives of benzene: 1-ethyl-2-methylbenzene

43. Derivatives of benzene: 1,2-dimethyl-4-propylbenzene

44. For your homework:If a halogen is attached, use the following prefixes: fluoro- chloro-bromo-iodo- (instead of methyl-, ethyl-, propyl-, etc.)