Organic Chemistry 1

The Chemistry of carbon compounds. 2

Organic Chemistry The Chemistry of carbon compounds. We will look at: (1) Naming of simple compounds. 3

Organic Chemistry The Chemistry of carbon compounds. We will look at: (1) Naming of simple compounds. (2) Some simple reactions. 4

Organic Chemistry The Chemistry of carbon compounds. We will look at: (1) Naming of simple compounds. (2) Some simple reactions. (3) Some simple properties. 5

Organic Chemistry The Chemistry of carbon compounds. We will look at: (1) Naming of simple compounds. (2) Some simple reactions. (3) Some simple properties. (4) Some applications will be discussed. 6

Naming simple organic compounds 7

Organic compounds are organized in different families, and each family has a root name. 8

Naming simple organic compounds Organic compounds are organized in different families, and each family has a root name. Compounds derived from the starting members in the family have their name based on the parent compound from which they are derived. 9

hydrocarbons The key compounds for naming are the hydrocarbons. 10

hydrocarbons The key compounds for naming are the hydrocarbons. There are three basic classifications and some important secondary classifications. 11

hydrocarbons The key compounds for naming are the hydrocarbons. There are three basic classifications and some important secondary classifications. (1) Alkanes 12

hydrocarbons The key compounds for naming are the hydrocarbons. There are three basic classifications and some important secondary classifications. (1) Alkanes (2) Alkenes 13

hydrocarbons The key compounds for naming are the hydrocarbons. There are three basic classifications and some important secondary classifications. (1) Alkanes (2) Alkenes (3) Alkynes 14

Prefix system used to name inorganic compounds. This is also used for organic compounds to name the number of substituents. The base names for the alkanes with five or more C atoms are derived directly from these names. 15 numberprefix 1mon* 2di 3tri 4tetra 5penta 6hexa 7hepta 8octa 9nona 10deca *Often not employed.

Prefix system used to name the number of carbon atoms in the longest chain of organic compounds. Note that the ones in blue do not follow from the first four prefixes in the previous table. These entries are sometimes termed the roots for the number of C atoms. 16 numberprefix 1meth 2eth 3prop 4but 5pent 6hex 7hept 8oct 9non 10dec

Names for organic compounds break up into two groups: 17

Names for organic compounds break up into two groups: Non-systematic (trivial) 18

Names for organic compounds break up into two groups: Non-systematic (trivial) Systematic (This will be our focus, though some of the common names will be mentioned.) 19

Names for organic compounds break up into two groups: Non-systematic (trivial) Systematic (This will be our focus, though some of the common names will be mentioned.) Example: H 2 O The non-systematic name is water. The systematic name is dihydrogen oxide. 20

Number of bonds For the following atoms the typical number of bonds from each atom is as follows: Atom Number of bonds H 1 C 4 21

Number of bonds For the following atoms the typical number of bonds from each atom is as follows: Atom Number of bonds H 1 C 4 O 2 N 3 22

Number of bonds For the following atoms the typical number of bonds from each atom is as follows: Atom Number of bonds H 1 C 4 O 2 N 3 (Note: there are exceptions) 23

The Alkanes 24

The Alkanes top priority family As far as naming is concerned, the alkanes are the top priority family. 25

The Alkanes top priority family As far as naming is concerned, the alkanes are the top priority family. Many other names are based on the names used for this group of compounds. 26

The Alkanes top priority family As far as naming is concerned, the alkanes are the top priority family. Many other names are based on the names used for this group of compounds. The alkanes have the general formula C n H 2n+2 where n = 1, 2, 3, …. 27

Formula Name CH 4 methane 28

Formula Name CH 4 methane CH 3 CH 3 ethane 29

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane 30

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 CH 2 CH 2 CH 3 butane 31

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 CH 2 CH 2 CH 3 butane CH 3 CH 2 CH 2 CH 2 CH 3 pentane 32

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 CH 2 CH 2 CH 3 butane CH 3 CH 2 CH 2 CH 2 CH 3 pentane CH 3 CH 2 CH 2 CH 2 CH 2 CH 3 hexane 33

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 CH 2 CH 2 CH 3 butane CH 3 CH 2 CH 2 CH 2 CH 3 pentane CH 3 CH 2 CH 2 CH 2 CH 2 CH 3 hexane CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 heptane 34

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 CH 2 CH 2 CH 3 butane CH 3 CH 2 CH 2 CH 2 CH 3 pentane CH 3 CH 2 CH 2 CH 2 CH 2 CH 3 hexane CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 heptane CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 octane 35

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 CH 2 CH 2 CH 3 butane CH 3 CH 2 CH 2 CH 2 CH 3 pentane CH 3 CH 2 CH 2 CH 2 CH 2 CH 3 hexane CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 heptane CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 octane CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 nonane 36

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 CH 2 CH 2 CH 3 butane CH 3 CH 2 CH 2 CH 2 CH 3 pentane CH 3 CH 2 CH 2 CH 2 CH 2 CH 3 hexane CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 heptane CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 octane CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 nonane CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 decane 37

Formula Name CH 4 methane 38

Formula Name CH 4 methane CH 3 CH 3 ethane 39

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane 40

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 (CH 2 ) 2 CH 3 butane 41

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 (CH 2 ) 2 CH 3 butane CH 3 (CH 2 ) 3 CH 3 pentane 42

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 (CH 2 ) 2 CH 3 butane CH 3 (CH 2 ) 3 CH 3 pentane CH 3 (CH 2 ) 4 CH 3 hexane 43

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 (CH 2 ) 2 CH 3 butane CH 3 (CH 2 ) 3 CH 3 pentane CH 3 (CH 2 ) 4 CH 3 hexane CH 3 (CH 2 ) 5 CH 3 heptane 44

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 (CH 2 ) 2 CH 3 butane CH 3 (CH 2 ) 3 CH 3 pentane CH 3 (CH 2 ) 4 CH 3 hexane CH 3 (CH 2 ) 5 CH 3 heptane CH 3 (CH 2 ) 6 CH 3 octane 45

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 (CH 2 ) 2 CH 3 butane CH 3 (CH 2 ) 3 CH 3 pentane CH 3 (CH 2 ) 4 CH 3 hexane CH 3 (CH 2 ) 5 CH 3 heptane CH 3 (CH 2 ) 6 CH 3 octane CH 3 (CH 2 ) 7 CH 3 nonane 46

Formula Name CH 4 methane CH 3 CH 3 ethane CH 3 CH 2 CH 3 propane CH 3 (CH 2 ) 2 CH 3 butane CH 3 (CH 2 ) 3 CH 3 pentane CH 3 (CH 2 ) 4 CH 3 hexane CH 3 (CH 2 ) 5 CH 3 heptane CH 3 (CH 2 ) 6 CH 3 octane CH 3 (CH 2 ) 7 CH 3 nonane CH 3 (CH 2 ) 8 CH 3 decane 47

Alkyl groups 48

Alkyl groups Formula Name 49

Alkyl groups Formula Name CH 3 methyl 50

Alkyl groups Formula Name CH 3 methyl CH 3 CH 2 ethyl 51

Alkyl groups Formula Name CH 3 methyl CH 3 CH 2 ethyl CH 3 CH 2 CH 2 n-propyl 52

Alkyl groups Formula Name CH 3 methyl CH 3 CH 2 ethyl CH 3 CH 2 CH 2 n-propyl CH 3 (CH 2 ) 2 CH 2 n-butyl 53

Alkyl groups Formula Name CH 3 methyl CH 3 CH 2 ethyl CH 3 CH 2 CH 2 n-propyl CH 3 (CH 2 ) 2 CH 2 n-butyl CH 3 (CH 2 ) 3 CH 2 n-pentyl 54

Alkyl groups Formula Name CH 3 methyl CH 3 CH 2 ethyl CH 3 CH 2 CH 2 n-propyl CH 3 (CH 2 ) 2 CH 2 n-butyl CH 3 (CH 2 ) 3 CH 2 n-pentyl Ending change: ane yl (or add yl to the root names) 55

In the previous list “n” stands for normal. In this case the bond is from the first carbon of the longest chain. 56

In the previous list “n” stands for normal. In this case the bond is from the first carbon of the longest chain. Three other prefixes that occur commonly are: sec- short for secondary 57

In the previous list “n” stands for normal. In this case the bond is from the first carbon of the longest chain. Three other prefixes that occur commonly are: sec- short for secondary tert- short for tertiary 58

In the previous list “n” stands for normal. In this case the bond is from the first carbon of the longest chain. Three other prefixes that occur commonly are: sec- short for secondary tert- short for tertiary iso (no hyphen is used) 59

In the previous list “n” stands for normal. In this case the bond is from the first carbon of the longest chain. Three other prefixes that occur commonly are: sec- short for secondary tert- short for tertiary iso (no hyphen is used) Examples: 60 sec-butyl

In the previous list “n” stands for normal. In this case the bond is from the first carbon of the longest chain. Three other prefixes that occur commonly are: sec- short for secondary tert- short for tertiary iso (no hyphen is used) Examples: 61 sec-butyltert-butyl

In the previous list “n” stands for normal. In this case the bond is from the first carbon of the longest chain. Three other prefixes that occur commonly are: sec- short for secondary tert- short for tertiary iso (no hyphen is used) Examples: 62 sec-butyltert-butylisobutyl

The term isoalkane is used to denote a branched chain alkane with a methyl group attached to the penultimate carbon atom of the main chain. 63

The term isoalkane is used to denote a branched chain alkane with a methyl group attached to the penultimate carbon atom of the main chain. As the number of carbon atoms increase, the prefixes become less useful, because an increasingly large number of prefixes would be needed. In this case, the standard numbering scheme (described about nine slides later) is used. 64

Structures of some alkanes 65

Structures of some alkanes 66

Structures of some alkanes 67

Structures of some alkanes 68

Structures of some alkanes 69

Structures of some alkanes These are straight chain examples. 70

Structures of some alkanes These are straight chain examples. Note that the alkanes have only single bonds. 71

Branched alkanes 72

Branched alkanes 73

Branched alkanes

Branched alkanes methylbutane (the 2 is a bit redundant) 75

Branched alkanes methylbutane (the 2 is a bit redundant) Number the longest chain so as to give the lowest number to the substituent (in this case a methyl group) off the main chain. 76

77

,3-dimethylpentane 79

80

Note: there is a methyl and an ethyl group off the main chain. 81

Note: there is a methyl and an ethyl group off the main chain. 82

and 6 bigger than 3 and 4 – so this is wrong numbering Note: there is a methyl and an ethyl group off the main chain. 83

Note: there is a methyl and an ethyl group off the main chain. 84

3-methyl-4-ethyloctane (complexity order) Note: there is a methyl and an ethyl group off the main chain. 85

3-methyl-4-ethyloctane (complexity order) 4-ethyl-3-methyloctane (alphabetical order) Note: there is a methyl and an ethyl group off the main chain. 86

Summary of the simple rules to name an alkane. Summary of the simple rules to name an alkane. Prefix + root + suffix 87

Ways of depicting an alkane Ways of depicting an alkane (p. 578) 88

The impact of free rotation about carbon – carbon single bonds. 89

Exercise: Draw the structures of (1) 2,2,3-trimethylbutane (2) 4-ethyl-2-methylnonane (2-methyl-4-ethylnonane) (3) 2,4-dimethyloctane 90

Physical properties of the alkanes The series of straight-chain alkanes shows a very smooth gradation of physical properties. As the series is ascended, each additional CH 2 group contributes a fairly constant increment to the boiling point and to the density – and to a lesser extent to the melting point. This makes it possible to estimate the properties of an unknown member of the series from those of its neighbors. 91

Alkenes 92

Alkenes These are hydrocarbons with at least one or more double bonds. 93

Alkenes These are hydrocarbons with at least one or more double bonds. The parent alkanes are used to name the alkene family of compounds. 94

Alkenes These are hydrocarbons with at least one or more double bonds. The parent alkanes are used to name the alkene family of compounds. The name ending change is: ane ene 95

alkane alkene structure ethane ethene 96

alkane alkene structure ethane ethene propane propene 97

alkane alkene structure butane butene 98

alkane alkene structure butane butene In this case there are three possible compounds. 99

alkane alkene structure butane butene In this case there are three possible compounds. 1-butene 100

alkane alkene structure butane butene In this case there are three possible compounds. 1-butene The number 1 indicates on which carbon the double bond starts. 101

alkane alkene structure butane butene In this case there are three possible compounds. 1-butene The number 1 indicates on which carbon the double bond starts. 2- butene 102

alkane alkene structure butane butene In this case there are three possible compounds. 1-butene The number 1 indicates on which carbon the double bond starts. 2- butene 103

alkane alkene structure butane butene In this case there are three possible compounds. 1-butene The number 1 indicates on which carbon the double bond starts. 2- butene cis-2-butene trans-2-butene 104

Z and E isomers Some cases arise in which it is very difficult to name a compound unambiguously, e.g. 105

Z and E isomers Some cases arise in which it is very difficult to name a compound unambiguously, e.g. 106

Z and E isomers Some cases arise in which it is very difficult to name a compound unambiguously, e.g. Is this a cis or trans compound? 107

Z and E isomers Some cases arise in which it is very difficult to name a compound unambiguously, e.g. Is this a cis or trans compound? A way to sort out this problem is to use the symbols 108

Z and E isomers Some cases arise in which it is very difficult to name a compound unambiguously, e.g. Is this a cis or trans compound? A way to sort out this problem is to use the symbols Z (zusammen = together) 109

Z and E isomers Some cases arise in which it is very difficult to name a compound unambiguously, e.g. Is this a cis or trans compound? A way to sort out this problem is to use the symbols Z (zusammen = together) E(entgegen = opposite) 110

Rules 1. Compare the two groups on one carbon atom of the carbon-carbon double bond. 111

Rules 1. Compare the two groups on one carbon atom of the carbon-carbon double bond. 2. Assign the two groups priorities using the Cahn- Ingold-Prelog rules for R and S configurations. 112

Rules 1. Compare the two groups on one carbon atom of the carbon-carbon double bond. 2. Assign the two groups priorities using the Cahn- Ingold-Prelog rules for R and S configurations. 3. Repeat steps 1 and 2 for the second carbon of the carbon-carbon double bond. 113

Rules 1. Compare the two groups on one carbon atom of the carbon-carbon double bond. 2. Assign the two groups priorities using the Cahn- Ingold-Prelog rules for R and S configurations. 3. Repeat steps 1 and 2 for the second carbon of the carbon-carbon double bond. 4. If the two groups of highest priority are on the same side of the double bond, we have the Z isomer. If the two groups are on opposite sides we have the E isomer. 114

Arrange the atoms in decreasing order of atomic number, e.g. I, Br, Cl, S, P, F, O, N, C, H 115

Z-2-butene 116

Z-2-butene E-2-butene 117

Z-2-butene E-2-butene E-2-bromo-1-chloro-1-iodopropene 118

Z-2-butene E-2-butene E-2-bromo-1-chloro-1-iodopropene The group of highest priority on each C atom is circled. 119

Z-2-butene E-2-butene E-2-bromo-1-chloro-1-iodopropene The group of highest priority on each C atom is circled. 120

alkene condensed formula ethene CH 2 CH 2 121

alkene condensed formula ethene CH 2 CH 2 propene CH 2 CHCH 3 122

alkene condensed formula ethene CH 2 CH 2 propene CH 2 CHCH 3 1-butene CH 2 CHCH 2 CH 3 123

alkene condensed formula ethene CH 2 CH 2 propene CH 2 CHCH 3 1-butene CH 2 CHCH 2 CH 3 2-butene CH 3 CHCHCH 3 124

alkene condensed formula ethene CH 2 CH 2 propene CH 2 CHCH 3 1-butene CH 2 CHCH 2 CH 3 2-butene CH 3 CHCHCH 3 Note: it would not be clear from the formula for 2- butene whether this is the cis or trans compound. 125

alkene condensed formula ethene CH 2 CH 2 propene CH 2 CHCH 3 1-butene CH 2 CHCH 2 CH 3 2-butene CH 3 CHCHCH 3 Note: it would not be clear from the formula for 2- butene whether this is the cis or trans compound. This is a reason why structures are very useful! 126

It is possible to have more than one double bond present. For example: 1,3-butadiene 127

Alkynes 128

Alkynes The alkynes have one or more triple bonds. 129

Alkynes The alkynes have one or more triple bonds. The ending change is: ane yne 130

Alkynes The alkynes have one or more triple bonds. The ending change is: ane yne The alkenes and the alkynes are referred to as unsaturated hydrocarbons. 131

Alkynes The alkynes have one or more triple bonds. The ending change is: ane yne The alkenes and the alkynes are referred to as unsaturated hydrocarbons. Unsaturated hydrocarbon: A hydrocarbon having one or more double or triple bonds. 132

alkane alkyne structure ethane ethyne 133

alkane alkyne structure ethane ethyne propane propyne 134

alkane alkyne structure ethane ethyne propane propyne butane 1-butyne 135

alkane alkyne structure ethane ethyne propane propyne butane 1-butyne 2-butyne 136

alkyne condensed formula ethyne C 2 H 2 137

alkyne condensed formula ethyne C 2 H 2 propyne CHCCH 3 138

alkyne condensed formula ethyne C 2 H 2 propyne CHCCH 3 1-butyne CHCCH 2 CH 3 139

alkyne condensed formula ethyne C 2 H 2 propyne CHCCH 3 1-butyne CHCCH 2 CH 3 2-butyne CH 3 CCCH 3 140

alkyne condensed formula ethyne C 2 H 2 propyne CHCCH 3 (Writing C 3 H 4 would not be useful.) 1-butyne CHCCH 2 CH 3 2-butyne CH 3 CCCH 3 141

alkyne condensed formula ethyne C 2 H 2 propyne CHCCH 3 (Writing C 3 H 4 would not be useful. Why?) 1-butyne CHCCH 2 CH 3 2-butyne CH 3 CCCH 3 142

Explanation of why C 3 H 4 would not be useful. 143

Explanation of why C 3 H 4 would not be useful. Clearly, this could be propyne. 144

Explanation of why C 3 H 4 would not be useful. Clearly, this could be propyne. But it could also be 145

Explanation of why C 3 H 4 would not be useful. Clearly, this could be propyne. But it could also be 1,2-propadiene 146

Explanation of why C 3 H 4 would not be useful. Clearly, this could be propyne. But it could also be 1,2-propadiene (The numbering would be a bit redundant in this example.) 147

Cycloalkanes 148

Cycloalkanes The cyclo compounds have a ring of carbon atoms present in the compound. 149

alkane cycloalkane structure propane cyclopropane 150

alkane cycloalkane structure propane cyclopropane butane cyclobutane 151

152

153

154

155

Conformational possibilities for cyclohexane 156

157

158

Some substituents 159

Some substituents Substituent Name F fluoro 160

Some substituents Substituent Name F fluoro Cl chloro 161

Some substituents Substituent Name F fluoro Cl chloro Br bromo 162

Some substituents Substituent Name F fluoro Cl chloro Br bromo I iodo 163

Some substituents Substituent Name F fluoro Cl chloro Br bromo I iodo Note: the ending change ide o as in chloride to chloro 164

Name the following 165

Name the following

Name the following

Name the following

Name the following

Name the following 1. fluoromethane

Name the following 1. fluoromethane 2. 1,1-difluoroethane

Name the following 1. fluoromethane 2. 1,1-difluoroethane 3. 1-chloro-1,2-difluoropropane

Name the following 1. fluoromethane 2. 1,1-difluoroethane 3. 1-chloro-1,2-difluoropropane 4. 1,2,3-tribromobutane 173

Name the following 1. fluoromethane 2. 1,1-difluoroethane 3. 1-chloro-1,2-difluoropropane* 4. 1,2,3-tribromobutane* *(there is more than one form of this compound) 174

Some simple reactions of alkanes, alkenes, and alkynes 175

Some simple reactions of alkanes, alkenes, and alkynes Combustion: CH O 2 CO H 2 O 176

Some simple reactions of alkanes, alkenes, and alkynes Combustion: CH O 2 CO H 2 O When the products are CO 2 and H 2 O it is termed a complete combustion. 177

Some simple reactions of alkanes, alkenes, and alkynes Combustion: CH O 2 CO H 2 O When the products are CO 2 and H 2 O it is termed a complete combustion. With insufficient O 2, CO will be formed. E. g. 2 CH O 2 2 CO + 4 H 2 O 178

Some simple reactions of alkanes, alkenes, and alkynes Combustion: CH O 2 CO H 2 O When the products are CO 2 and H 2 O it is termed a complete combustion. With insufficient O 2, CO will be formed. E. g. 2 CH O 2 2 CO + 4 H 2 O This is called an incomplete combustion. 179