Functional Groups. Functional groups: special groups of atoms attached to a hydrocarbon skeleton; the most common sites of chemical reactivity.

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2 Functional Groups Functional groups: special groups of atoms attached to a hydrocarbon skeleton; the most common sites of chemical reactivity.

3 Organic halides: a hydrogen is replaced by a halogen fluoro-, chloro-, bromo-, iodo- 2-iodobutane

4 Organic halides: a hydrogen is replaced by a halogen fluoro-, chloro-, bromo-, iodo- 2,4-dibromo-1-hexene

5 Organic halides: a hydrogen is replaced by a halogen fluoro-, chloro-, bromo-, iodo- 1-bromo-2-chlorobenzene

6 Alcohols & phenols: contain the hydroxyl group (-OH) alcohols: at least 1 H on a hydrocarbon is replaced by OH phenols: at least 1 H on an aromatic ring is replaced by OH 2-propanol

7 Alcohols & phenols: contain the hydroxyl group (-OH) alcohols: at least 1 H on a hydrocarbon is replaced by OH phenols: at least 1 H on an aromatic ring is replaced by OH 3-methyl-1-butanol

8 Alcohols & phenols: contain the hydroxyl group (-OH) alcohols: at least 1 H on a hydrocarbon is replaced by OH phenols: at least 1 H on an aromatic ring is replaced by OH 1,2-butanediol

9 ethers: compounds in which an O atom is bonded to 2 organic groups: -C-O-Cmethoxymethane (dimethyl ether)

10 ethers: compounds in which an O atom is bonded to 2 organic groups: -C-O-Cmethoxypropane (methyl propyl ether)

11 ethers: compounds in which an O atom is bonded to 2 organic groups: -C-O-Cmethoxybenzene (methyl phenyl ether)

12 Carboxylic acids: compounds that contain the carboxyl group (general formula is R-COOH) butanoic acid

13 Carboxylic acids: compounds that contain the carboxyl group (general formula is R-COOH) ethanoic acid

14 Carboxylic acids: compounds that contain the carboxyl group (general formula is R-COOH) 3-methylpentanoic acid

15 Carboxylic acids: compounds that contain the carboxyl group (general formula is R-COOH) benzoic acid

16 amines: derivatives of ammonia (NH 3 ) in which 1 or more H atoms are replaced by organic groups (alkyl or aryl groups) ammonia

17 amines: derivatives of ammonia (NH 3 ) in which 1 or more H atoms are replaced by organic groups (alkyl or aryl groups) methylamine

18 amines: derivatives of ammonia (NH 3 ) in which 1 or more H atoms are replaced by organic groups (alkyl or aryl groups) trimethylamine

19 amines: derivatives of ammonia (NH 3 ) in which 1 or more H atoms are replaced by organic groups (alkyl or aryl groups) 2-aminobutane

20 amines: derivatives of ammonia (NH 3 ) in which 1 or more H atoms are replaced by organic groups (alkyl or aryl groups) 1-amino-3-propylcyclohexane

21 *aniline: the simplest aromatic amine aniline

22 *aniline: the simplest aromatic amine 3,5-dichloroaniline Naming it aniline make this carbon #1 by definition

23 *aniline: the simplest aromatic amine N,N-dimethylaniline

24 Summary of IUPAC rules for naming organic compounds IUPAC: International Union of Pure and Applied Chemistry International, non-governmental organization that is best known for its system of nomenclature, which is now recognized as the world authority in this field.

25 Rule #1: Identify the longest chain of carbon atoms a) The longest chain of carbon atoms gives the stem/root of the name as shown in the table below: # of C-atoms in longest chain Stem in IUPAC name 1 meth- CH 4, methane Example (C 2 H 2n+2 for alkanes) 2 eth- C 2 H 6, ethane 3 prop- C 3 H 8, propane 4 but- C 4 H 10, butane 5 pent- C 5 H 12, pentane 6 hex- C 6 H 14, hexane 7 hept- C 7 H 16, heptane 8 oct- C 8 H 18, octane 9 non- C 9 H 20, nonane

26 Rule #1: Identify the longest chain of carbon atoms b) If two chains have equal lengths, pick the one with more branch points.

27 Rule #2: Number the carbons in the main chain Number chain to minimize the position/number of the following in order of priority: a) thing you re naming the compound after (double bond if alkene; -OH group if alcohol, etc) a) note: for multiple double bonds -diene, -triene, -tetraene b) first branch/substituent group c) If both ends have the same first branching number, then number chain to minimize position of second branch (and then third and so on). d) if still in need of a tie breaker, minimize # of substituent group that comes first alphabetically Note: in cyclic and aromatic (benzene derivatives) compounds, no number needed if only one substituent.

28 Rule #3: Identify the functional group and attach appropriate suffix Note: the name for the stem/root is derived from the longest carbon chain, which may include the carbon of the functional group. Indicating position of the functional group: shown by a number inserted before the functional group ending. The number refers to the carbon atom to which the functional group is attached when the chain is numbered starting at the end that will give the smallest number to the group.

29 Class of compound alkane alkene alkyne alcohol aldehyde ketone carboxylic acid amine Functional group Suffix in IUPAC name -ane -ene -yne -anol -anal -anone -anoic acid -anamine

30 Rule #4: Identify the side chains or substituent groups Assign number of carbon at point of attachment. Side chain/ substituent group Prefix in IUPAC name Example -CH 3 methyl- 2-methylpropane -C 2 H 5 ethyl 3-ethylpentane -C 3 H 7 propyl- 4-propylheptane -F, -Cl, -Br, -I fluoro-, chloro-, bromo-, iodo- tetrachloromethane -NH 2 amino- 2-aminoethanioic acid

31 Rule #5: Assemble name as a single word #, substituent, root, suffix a) List substituents alphabetically (i.e. butyl- before methyl-) b) If multiples of one substituent are present: di-, tri-, tetra, etc. Note: di-, tri-, tetra, etc. aren t part of alphabetical name (triethyl- before dimethyl-) c) punctuation: commas between numbers; hyphens between numbers and letters; merged into one word (exception: acid = word #2 for carboxylic acids)