Naming Organic Halide Organic Halide: is a compound that contains one or more halogen atoms (F, Cl, Br, I) as part of its molecular structure.

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1 Naming Organic Halide Organic Halide: is a compound that contains one or more halogen atoms (F, Cl, Br, I) as part of its molecular structure. Organic halides have many important uses including: fire retardation, anaesthesia, plastics manufacturing, refrigeration/cooling systems, etc. Naming Alkyl Halides 1. Identify and name the longest continuous chain of carbon atoms. 2. Assign lowest possible numbers to the substituents (branches). 3. List the substituents in alphabetical order using appropriate prefixes. Branches: Fluorine =fluoro chlorine= chloro bromine= bromo iodine = iodo Apr 25 5:50 PM 1

2 Ex 1: Provide a IUPAC name for each structural formula. a. b. C. Apr 25 5:59 PM 2

3 D. E. F. May 1 6:27 PM 3

4 Ex 2: Write a structural formula for following compounds: a) 1 chloro 1,2 difluoroethane. c) 1 chloro 2,2 dimethylpropane b) 2 chloro 2 methylbutane d) 2 methyl 2,3 dibromopentane Apr 19 8:05 AM 4

5 Alcohols and Ethers Functional groups atoms or groups of atoms that give compounds their unique chemical and physical properties. Alcohols are defined by the functional group called hydroxyl (OH ). The general formula for an alcohol is R OH where R represents an alkyl group. Naming and Drawing Structural Formulas for Alcohols 1.The ol suffix in a chemical name identifies a compound as an alcohol; it signals the presence of a hydroxyl group. 2. Name the longest continuous chain like an alkane then change the e ending of the alkane name to ol. 3. Indicate the location of the hydroxyl group using the lowest possible number. Attach the number to the name with a hyphen. 4.If the alkyl group is branched, priority in the numbering of the parent goes to the location of the hydroxyl group. Apr 25 6:00 PM 5

6 Ex 1: Write the IUPAC names that correspond to these structural formulas. a. b. c. d. Apr 25 6:03 PM 6

7 Ex 2: Draw a structural formula for each alcohol. a. 2 propanol b. 3 pentanol c. 2 methyl 2 butanol Apr 25 6:11 PM 7

8 Alcohols: Compounds that possess more than one hydroxyl group are called polyalcohols. Phenol is an alcohol in which the hydroxyl group is a substituent of a benzene ring. The name consists of the root of the word phenyl (which is used to identify benzene rings) and the suffix ol which represents a hydroxyl group. Apr 25 6:13 PM 8

9 Properties of Alcohols A function of the hydrogen bonding associated with the highly polar "OH" bond. Short chain alcohols like methanol, ethanol, and propanols have the unique property of being soluble in nonpolar and polar solvents. This makes them very useful for cleaning oily, greasy, or waxy materials. The alkyl component of these alcohols dissolves in nonpolar oils, grease, or wax while the hydroxyl end dissolves easily in water. Feb 27 9:54 PM 9

10 higher melting and boiling points compared to corresponding aliphatic hydrocarbons is due to the strong hydrogen bonds that form between alcohol molecules and the slightly greater London dispersion forces due to the higher number of electrons per molecule. For example, ethane boils at 88.5 C whereas ethanol boils at 78.5 C. Feb 27 9:54 PM 10

11 Ethers are defined by the functional group known as ether ( O ). The general formula for an ether is R 1 O R 2 where R 1 and R 2 represent alkyl groups. In an ether, the alkyl groups can be the same or different. The alkyl groups are methyls ( CH 3 ). Naming and Drawing Structural Formulas for Ethers If they are different, name and list them in alphabetical order as one word and add the word ether to make a phrase. If they are the same, add the prefix di to the alkyl name, and then write the word ether to complete the phrase. Apr 28 11:27 AM 11

12 Ex 1: Provide a IUPAC name for each ether. ethylpropyl ether. ethylmethyl ether. diethyl ether. Apr 28 11:29 AM 12

13 Ex 2: Draw a structural formula for each ether. a. dimethyl ether b. butylmethyl ether Apr 28 11:34 AM 13

14 Properties of Ethers A function of the stable ether link between the alkyl groups. Aside from being highly flammable, ethers are generally unreactive. Ethers are volatile they evaporate more easily than alcohols because they lack hydrogen bonding. This property makes them useful as anaesthetics, propellants (in spray cans), and solvents for varnishes and lacquers. Ethers have lower melting and boiling points than their alcohol isomers because they lack hydrogen bonding. Feb 27 9:55 PM 14

15 Chemistry, Society and the Environment When a car engine doesn't get enough air (oxygen) some gasoline molecule are incompletely burned producing carbon monoxide, soot, and a rotten egg smell (sulfur compounds). The combination of unburned hydrocarbons, sulfur compounds, nitrous oxides, and the other emission products from automobile engines is responsible for most of the air pollution in large cities like Montreal, Toront and Vancouver. In many parts of North America, clean air laws are forcing petroleum refin to make cleaner gasolines. Refiners have responded by adding alcohols and/or ethers to gasoline. Gasohol, for example, is a blend of 10 15% ethano and 85 90% gasoline. Reformulated gasoline (RFG) contains at least 2% tertiary butylmethyl ether (MTBE). Feb 27 9:52 PM 15

16 MTBE is manufactured by reacting methanol with methylpropene. + It's highly branched structure makes it an even burning fuel that reduces an engine condition called "knock and ping"; however, the main reason it is added to gasoline is because it is an oxygenate. MTBE raises the oxygen content of gasoline. Oxygen helps the gasoline to burn more completely thereby reducing harmful tailpipe emissions such as carbon monoxide. Feb 27 9:52 PM 16

17 The use of MTBE also means less reliance on other octane enhancers like benzene (a known carcinogen) and sulfur compounds (which when burned contribute to the acid rain problem). Most refiners have chosen to use MTBE over other oxygenates primarily for its blending characteristics and for economic reasons. Incomplete combustion of gasoline is more common during the winter By law, the gasoline supplied to stations in certain North American cities must be 2.7% oxygen by mass. The higher oxygen content results in more complete combustion and less carbon monoxide pollution. It is sometimes sold under the marketing slogan "winter gas".ethanol or MTBE are used to bring the oxygen content of gasoline up to the legislated levels. May 16 11:04 PM 17

18 Because of its solubility in water, MTBE can pass quickly through soil contaminating groundwater. There is substantial controversy surrounding the use of MTBE because it is a suspected human carcinogen. Ethanol, commonly known as grain alcohol is also used as an octane enhancer. It has traditionally been made from the fermentation of sugars and starches derived from crops like corn. It is difficult to achieve high concentrations of ethanol in a fermentation chamber because the yeast that produces it is killed when the alcohol concentration approaches 15%. Large quantities of grain are needed to produce a relatively small amount of ethanol. Feb 27 9:53 PM 18

19 Aldehydes Aldehydes have a terminal carbonyl group ( C=O). that is, the carbonyl group is located at the end of the molecule. The general formula of an aldehyde is R CHO where R represents a single hydrogen atom or a chain of carbon atoms. The simplest aldehyde is methanal, H 2 CO. The carbon of the carbonyl group is the only carbon atom in the molecule. Apr 28 11:39 AM 19

20 Naming Aldehydes 1. Identify the longest continuous chain of carbon atoms (including the carbon atom in the carbonyl group). 2. Write the name of the corresponding alkane and replace the e ending of the alkane name with al. Apr 28 11:40 AM 20

21 Ex 1: Provide a name for each structural formula. Mar 11 3:52 PM 21

22 Ex 2: Provide structural formulas for these aldehydes. a. Heptanal b. 2 methylbutanal Apr 28 11:41 AM 22

23 Ketones :contain the functional group called carbonyl ( C=O); however, the carbonyl group in ketones is locate on a non terminal carbon. This means the simplest possible ketone is propanone: CH 3 COCH 3. Apr 28 11:45 AM 23

24 The general formula for ketones is R 1 CO R 2, where R 1 and R 2 represent alkyl groups. The carbon of the carbonyl group is counted as part of the carbon chain for naming purposes. The shortest carbon chain in a ketone is three carbons in length. Mar 11 3:55 PM 24

25 Naming Ketones 1.Identify the longest continuous chain of carbon atoms (including the carbon atom in the carbonyl group). 2.Write the name of the corresponding alkane and replace the e ending of the alkane name with one. 3.If the carbon chain is five carbon atoms or longer, indicate the position of the carbonyl group by assigning i the lowest number possible. Apr 28 11:47 AM 25

26 Ex 1: Provide names for these ketones. Mar 11 3:55 PM 26

27 Ex 2: Provide structural formulas for these ketones. a. 2 butanone b. 3 ethyl 4 methyl 2 hexanone Apr 28 11:48 AM 27

28 Some Properties and Uses of Aldehydes and Ketones Many aldehydes and ketones have pleasant odours. For example, benzaldehyde gives almonds their distinctive flavour while cinnamaldehyde gives the aroma associate with oil of cinnamon. These compounds, like many other aldehydes and ketone occur in nature but they may also be synthesized in a lab from alcohols. May 17 10:16 PM 28

29 Methanal (commonly known as formaldehyde) is by far the most common aldehyde. As formalin (a 40% solution of methanal and water), it is used as a tissue preservative in biology and hospital laboratories and as embalming fluid in funeral homes. Mar 11 3:57 PM 29

30 Perhaps the most widely recognized ketone is propanone (commonly known as acetone). It is found in substances such as nail polish remover, varnish, and liquid cleaners. Propanone, like some alcohols, dissolves polar and nonpolar solutes and is commonly used as a cleaner in organic chemistry laboratories. Mar 2 9:08 AM 30

31 Organic Acids (Carboxylic Acids) The most familiar is ethanoic acid (acetic acid or simply vinegar). They are also called fatty acids. Fatty acids are long chain hydrocarbons that have a carboxyl group one end which are found in animal fats and vegetable oils. C 17 H 35 COOH Apr 28 11:50 AM 31

32 The functional group that gives organic acids, their chemical and physical properties is the carboxyl group, COOH. The general formula for the carboxylic acids is RCOOH where R represents a hydrogen atom or alkyl group. Mar 2 9:13 AM 32

33 Naming Carboxylic Acids 1. Name the longest continuous chain of carbons, including the carbon of the carboxyl group, using an alkane name. 2. The carbon atom in the carboxyl group is carbon #1. 3. Replace the e ending of the hydrocarbon name with the suffix oic and add the word acid to the first name to make a phrase. May 17 10:13 PM 33

34 Ex 1: Provide a IUPAC name for each structural formula propanoic acid 3 ethylpentanoic acid Mar 11 3:59 PM 34

35 Ex 2: Draw a structural formula for each carboxylic acid. a. butanoic acid b. 2 methylbutanoic acid Apr 28 1:52 PM 35

36 Esters Esters are abundant in nature. Many of the pleasant odors you associate with flowers and berries are due to esters a are the scents of bath oils, shampoos, soaps, and room fresheners, artificially favored,etc. The functional group of an ester is Apr 28 1:53 PM 36

37 Esters are produced by reacting carboxylic acids with alcohols. Mar 11 4:00 PM 37

38 The general formula of an ester is RCOOR' where R represents hydrogen or a carbon chain/alkyl group and R' represents an alkyl group. Apr 28 1:55 PM 38

39 Naming Esters 1. Count to find the number of carbon atoms in the OR' component of the structural formula (the part derived from an alcohol) and assign it an alkyl group name. 2. Count the number of carbon atoms in the R C=O component of the structural formula (the part derived from the carboxylic acid) and assign it an alkane name with an oate ending in place of the oic ending. Combine the names to make a phrase. Mar 11 4:00 PM 39

40 Ex 1: Provide a IUPAC name for each structural formula. a. propyl propanoate. b. methyl butanoate. Apr 28 1:55 PM 40

41 Ex 2: Provide a structural formula for each ester. a. butyl ethanoate b. phenyl ethanoate Mar 11 4:01 PM 41

42 Jun 10 11:58 AM 42

43 Amines Amines are derived from ammonia (NH 3 ) when more of the hydrogen atoms are replaced by a hydrocarbon group. A nitrogen atom is the functional group. One hydrocarbon group bonded to an amino group ( NH 2 ). These amines have the general formula RNH 2 where R represents an alkyl group. R NH 2 To name an amine, identify the alkyl group and add the suffix amine to its name. Apr 28 1:58 PM 43

44 Ex 1: Name this structural formula. butylamine. Ex: 2: Draw a structural formula for ethylamine. May 17 10:28 PM 44

45 use notebook Amino group is a branch ( NH 2 ). Naming amine 1. Name the longest continuous chain of carbons, using an alkane name. 2. The carbon atom with the amino group the lowest possible position in the longest chain. 3. Replace the e ending of the hydrocarbon name with the suffix amine. May 8 2:28 PM 45

46 use notebook Ex1: Name these structural formulas. May 8 2:37 PM 46

47 May 16 11:15 AM 47

48 use notebook Ex2: Draw the structural formulas. a) 2 propanamine b) 3 heptanamine May 8 2:52 PM 48

49 use notebook d) 2 bromo 5 methyl 4 hexanamine e) 5 ethyl 4 methyl 3 octanamine May 15 10:12 PM 49

50 Amides The functional group of an amide consists of a carbonyl group and an amino group. The general formula for an amide is RCONH 2 where R represents hydrogen or an alkyl group. To name an amide, write the name for the carbon chain containing the carbonyl group, drop the e ending, and add the suffix amide. Apr 28 2:03 PM 50

51 Ex 1: Name this structural formula. butanamide. Ex 2: Write a structural formula for propanamide. Apr 28 2:05 PM 51

52 Naming Amides with branches 1. Count to find the number of carbon atoms in the NR' component of the structural formula (the part derived from an amine) and assign it an alkyl group name. 2. Count the number of carbon atoms in the RCO component of the structural formula (the part derived from the carboxylic acid) and assign it an alkane name, drop the e ending, and add the suffix amide. Combine the names to make a phrase. May 17 10:32 PM 52

53 Ex 3: Name these structural formulas. a. b. N methylethanamide N,N dimethylpropanamide May 17 10:31 PM 53

54 Name these structural formulas. a. N,N diethylethanamide b. N,N ethylmethylethanamide May 17 10:34 PM 54

55 Amines and amides have unpleasant scents. Urea is one of many common examples. Amino Acids Amino acids are the building blocks of proteins. Proteins are the stuff of life! Apr 28 2:06 PM 55

56 May 8 9:49 AM 56