CHEMISTRY OF THE COVALENT COMPOUNDS OF CARBON

1. Organic Chemistry C H B N O F Si P S Cl Br I CHEMISTRY OF THE COVALENT COMPOUNDS OF CARBON COMBINED WITH A FEW OTHER COMMON ELEMENTS: H B N O Si P S F Cl Br I

2. Millions of things contain organic molecules….

3. C C C C C C C C C C C C C C C C UNIQUE PROPERTIES OF CARBON Carbon is TETRAVALENT - which means it bonds four times…. Carbon is one of the few elements that can form chains with itself… C-C-C-C-C-C-C-C-C Carbon can also form BRANCHED NETWORKS and RINGS

4. Most organic molecules contain C-C and C-H bonds which are non-polar…water, which has slight charge, is polar Because of this, most organic molecules do not dissolve in water – For example, oil and water do not mix! Most organic molecules are gases or quickly evaporating liquids at room temperature because they have no charge – they have weak physical bonds (London Dispersion bonds) Organic molecules will not have charge unless they contain a bond with polarity Those that do have slightly charged bonds – like C-O or O-H bonds (as in alcohols) dissolve well in water! Most organic molecules have no charge…. Water - has slight charge…is a liquid Water - has slight charge…is a liquid NO ATTRACTION ATTRACTION! Methane – has no charge… is a gas Methanol – Has slight charge – is a liquid and dissolves well in water

5. Hydrocarbons – contain hydrogen and carbon bonds Aliphatic hydrocarbons – chains of carbons and hydrogens Functional groups – altered hydrocarbons Aromatic hydrocarbons – contain benzenec Alkanes – all single bonds Alkenes – has some double bonds Alkynes has some triple bonds • Ether • Ester • Aldehyde • Ketone • Carboxylic acid • alcohol saturated unsaturated

6. Aliphatic Hydrocarbons • Hydrocarbons are compounds composed of carbon and hydrogen in chains • Aliphatic – meaning chains of carbons – either straight or branched chains

7. Aliphatic Hydrocarbons • Unsaturated: contains carbon-carbon double or triple bonds. • Saturated: contains all carbon-carbon single bonds.

8. Common Hydrocarbon Types only single bonds ALKANES CnH2n+2 at least one double bond ALKENES CnH2n at least one triple bond ALKYNES CnH2n-2

9. Structural Formulas – show the structure of the atoms Unbranched (“linear”) Alkane Branched Alkane Structural Formulas some bonds shown Condensed Structural Formulas CH3CH2CH2CH2CH3 CH3CH(CH3)CH2CH(CH3)CH3 Molecular Formula – Tells me nothing about Structure – just how many of each element there are! C7H16 C5H12 CH3CH(CH3)CH2CH(CH3)CH3

10. H H H C C C C H H H H H H H C C C H H Condensed Notation CH3CH2-CH=CH2 CH3CH2CH=CH2 Alkene H-C C-CH3 HC CCH3 or Alkyne CH CCH3

11. Condensed Notation EVEN COMPLICATED BRANCHED STRUCTURES CAN BE WRITTEN ON A SINGLE LINE for this reason many handbooks use condensed notation CH3CH(CH3)CH(CH2CH3)CH2CH3 Branched Alkane note use of parentheses - these atoms are attached to the Carbon atom that they follow

12. Skeleton Notation

13. Cyclic Molecules • For some molecules, the carbon chain may close on itself to form a ring. • These types of substances are called cyclic molecules. • These do not follow the general formulas for alkanes, alkenes, and alkynes (CnH2n+2, CnH2n, and CnH2n-2)

14. Examples of Cyclic Molecules Testosterone

15. How to name compounds… Prefixes for organic are different than traditional naming… Endings: -ane = single bonds – ene = double bonds – yne = triple bonds

16. Groups are named according to the number of carbon chains in the group…. The group has the ending –yl if it is a carbon group – the group has the ending –o if it is a halogen -Cl chloro group -CH2CH3 ethyl group -CH3 methyl group C

17. Six carbons…. Hex…. Longest chain….? All single bonds…. -ane…. Bond types….? -CH3 = methyl Attached groups…? Number from what side…? The right…. The group is attached to carbon 3, and not carbon 4 Why…? 3-methyl hexane

18. Nomenclature for other types of hydrocarbons… 1, 1 dimethyl cyclobutane

19. Longest chain…? • Did you include the entire double bond…? • Start numbering from what end…? • Is the double bond or attached groups more important…? • How many groups are attached…? • What are they? • Remember to report the groups alphabetically….! 5-chloro 7-methyl - 3 – nonene

20. Name this sucker….! 4-butyl 2-methyl 1, 5 heptene-yne

21. Important things to remember… • Double and triple bonds are most important when counting the longest chain • Always include both the double and triple bond in the longest chain – even if it isn’t the most number of carbons! • Start counting from the end closest to the double or triple bond – whichever has the lowest number • If there is a tie, and only then, do double bonds take priority over triple bonds • If there isn’t a double or triple bond, find the longest continuous chain of carbons, and start counting from the end closest to an attached group – • It doesn’t matter what the group is – all groups have the same importance – CH3, -CH2-CH3, -Cl, etc. • If there is a tie, start counting from the end that has the most groups on the lowest number Which end do you number from?

22. http://www.chem.ucalgary.ca/courses/351/orgnom/index.html http://www.cem.msu.edu/~reusch/VirtualText/nomen1.htm http://en.wikipedia.org/wiki/IUPAC_nomenclature_of_organic_chemistry http://chemistry.boisestate.edu/people/richardbanks/organic/nomenclature/organicnomenclature1.htm http://www.chembio.uoguelph.ca/educmat/chm19104/nomenclature/quizes.html http://www.quia.com/jg/65803.html http://eppe.tripod.com/orgtable.htm http://www.cem.msu.edu/~reusch/VirtualText/Questions/Nomencl/nomencl.htm http://www.chemguide.co.uk/atoms/bonding/vdw.html • Great websites for tutorials….

23. Boiling points of various hydrocarbons… Why do they increase…?

24. Boiling point as we halogenate, or add a halogen to a hydrocarbon, goes…. • Up! Why???? • Methane = -1620C • Fluoromethane = -78.20C • Difluoromethane = -51.60C • Trifluoromethane = -50C • Tetrafluoromethane = -1280C

25. Why would we want to halogenate a hydrocarbon…? • Does it matter what halogen you add…?

26. Halogenated hydrocarbons are used as refrigerants… 1.The compressor compresses cool Freon gas, causing it to become hot, high-pressure Freon gas (red in the diagram above). 2.This hot gas runs through a set of coils so it can dissipate its heat, and it condenses into a liquid. 3.The Freon liquid runs through an expansion valve, and in the process it evaporates to become cold, low-pressure Freon gas (light blue in the diagram above). 4.This cold gas runs through a set of coils that allow the gas to absorb heat and cool down the air inside the building.

27. Structural Isomers… Molecules that have the same molecular formula, meaning same numbers of carbons and hydrogens, but different structures… Isomers of octane…..there are 18 different arrangements! 2-methyl heptane Are these both octane though? Octane

28. Structural Isomers… The problem is that some chemists generically refer to both of the following compounds as octane, since they both contain 8 carbons and 18 hydrogens… 2-methyl heptane Octane The official naming system, the IUPAC naming system, does not call both of these molecules octane though! Look at these two molecules - both of these molecules are generically referred to as structural isomers of hexane, because they both have 6 carbons and 14 hydrogens (C6H14). They don’t have the same IUPAC name at all – they are totally different molecules, with totally different properties!

29. Geometric Isomers Cis means same side… Trans means opposite side… • Molecules that have the same molecular formula, but differ in how groups attached to the double bond are oriented • Must have a double bond, and different groups on both the left and right sides!

30. Geometric Isomers Both are the same molecule! 1,2 dichloroethane 2 different molecules: trans – 1,2 dichloroethene cis – 1,2 dichloroethene • This doesn’t happen with a single bond… • The atoms are free to rotate around the single bond, to form both molecules…. • With a double bond, the atoms are locked into place by the p orbitals bonding in the double bond!

31. Geometric Isomers Same molecule.. Isomers! Isomers! Same molecule.. • To have geometric isomers: • You must have a double bond in the molecule • You must have two different groups on the left hand side of the bond, and two different groups on the right hand side of the double bond. The left side groups do not have to be the same as the right side groups! Which are isomers, and which are the same molecule…?

32. Stereoisomers • Molecules that have the same molecular formula, have the same sequence of bonded atoms, but differ in their 3-d orientation! • Stereoisomers can be non-superimposable mirror images! • We call the carbons that they are attached to chiral, or asymmetric! • This means they are non-symmetrical! • Our hands are chiral!

33. - In nature, only one stereoisomer of biological molecules is usually present (example – amino acids)- In medicine, different stereoiomers of a compound may have substantially different biological effects.- For example, for certain cancer drugs, such as cisplatin and leucovorin, only one of the two stereoisomers are effective in combating cancer – the other stereoisomer is either ineffective or poisonous!- Robutissin contains D-methorphan – a powerful cough suppressant – the stereoisomer of this molecule, L-methorphan, is an illegal opiate that has totally different effects in the body!- How do they separate stereoisomers, if their only difference is the fact that they are mirror images? Chemically, they look nearly identical! The two stereoisomers of the amino acid alanine… D-methorphan L-methorphan

34. Benzene….

35. Any compound containing benzene is called an aromatic or arene compound… • Any compound containing straight or branched chains of carbons is called aliphatic… Notice the resonance in the benzene ring…

36. Common benzene compounds toluene anisole aniline xylene phenol cresol styrene benzoic acid salicylic acid

37. Benzene rings with two attached groups use a special naming system…They use the ortho, meta, and para system…Ortho (o) means one apart…Meta (m) means two apart…Para (p) means three apart…This only applies to benzene rings with TWO groups… p-bromo phenol o-chloro toluene

39. 1,4 dibromo aniline Names…? m-ethyl anisole 2-chloro 3-ethyl toluene

40. Benzene can also be called phenyl when you want to treat it as an attached group….either name is acceptable! 3-ethyl-2-phenyl pentane 2-chloro-2-phenyl heptane

41. 1,3,5 tri-nitro toluene…TNT! Dichloro-Diphenyl-Trichloroethane DDT…

42. http://www.chem.ucalgary.ca/courses/351/orgnom/functional/func.htmlhttp://www.chem.ucalgary.ca/courses/351/orgnom/functional/func.html • Functional Group Name Ending • Alcohol -ol • Aldehyde -al • Ketone - one • Ether - oxy (small) normal chain (large) • Carboxylic Acid - oic acid • Ester -yl -oate

43. 1-butanal Aldehyde… 2-butanol alcohol… aldehyde… 1-pentanal 1-phenyl 1-butanone ketone… Carboxylic acid… 1-propanoic acid

44. 1-butanoic acid Carboxylic acid… 3-hexanone ketone… ester… Ethyl butanoate 2-ethoxy propane ether… 5-chloro 3-hexanone ketone…

45. Methanal Formaldehyde (nickname!) Ethanoic acid Acetic acid (nickname!) Methanoic acid Formic Acid (nickname!)

46. Example Structures of complex organic molecules… nicotine cholesterol Meth amphetamine mescaline caffeine

47. Think nomenclature is hard…? ZITHROMAX (azithromycin tablets and azithromycin for oral suspension) contain the active ingredient azithromycin, an azalide, a subclass of macrolide antibiotics, for oral administration. Azithromycin has the chemical name (2R,3S,4R,5R,8R, 10R,11R,12S,13S,14R)-13-[(2,6-dideoxy-3-C-methyl-3-O-methyl-α-L-ribo-hexopyranosyl) oxy]-2-ethyl-3,4,10-trihydroxy-3,5,6,8,10,12,14-heptamethyl-11-[[3,4,6-trideoxy-3- (dimethylamino)-β-D-xylo-hexopyranosyl]oxy]-1-oxa-6-azacyclopentadecan-15-one. Azithromycin is derived from erythromycin; however, it differs chemically from erythromycin in that a methyl-substituted nitrogen atom is incorporated into the lactone ring. Its molecular formula is C38H72N2O12, and its molecular weight is 749.00.