Presentation on theme: "Organic Chemistry Essentials Chemistry of carbon compounds Carbon can form 4 covalent bonds with other atoms. This allows it to make millions of different."— Presentation transcript:
Organic Chemistry Essentials Chemistry of carbon compounds Carbon can form 4 covalent bonds with other atoms. This allows it to make millions of different compounds. Carbon can form single, double, and triple bonds.
Hydrocarbon compound containing only hydrogen and carbon Ex. CH 4 C 2 H 6
Hydrocarbon derivative compound with some hydrogen atoms replaced by other elements (O, N, F, Cl, Br, I) ex. CH 3 Br
Straight chained hydrocarbon Ex. CH 3 CH 2 CH 2 CH 2 CH 2 CH 3 or C 6 H 14
Branched hydrocarbon CH 3 CH 3 CH 2 CHCH 2 CH 3 or C 6 H 14
Saturated hydrocarbon no double or triple bonds
Unsaturated hydrocarbon contains double and/or triple bonds not “saturated” with hydrogen
Alkenes contain at least one double bond name ends in -ene general formula: C n H 2n
Alkynes contain at least one triple bond name ends in -yne general formula: C n H 2n-2
Nomenclature naming system IUPAC (International Union of Pure and Applied Chemistry)
Rules for naming alkanes 1. Name the longest carbon chain in the structure. If the chain is cyclic, include the prefix cyclo. 2. Name, in alphabetical order, the kinds of groups which are attached to the chain you named in step 1. Use the appropriate prefix, such as di-, tri-, tetra-, etc., to indicate how many of each group are present.
3. Number the carbon atoms in the longest chain consecutively from the end of the chain which allows the attached groups to have the lowest numbers possible. Assign to each group you named in step 2 the number(s) indicating its position(s) on the main chain.
Rules for naming alkenes and alkynes 1.Name the longest carbon chain containing the carbon-carbon double or triple bond. The name of the longest chain ends in – ene for an alkene; in –yne for an alkyne. The position of the double or triple bond in the carbon chain is indicated by a number before the name of the chain. 2.Name the groups attached as in alkanes.
3. When assigning numbers to atoms in the chain, start numbering from the end of the chain closest to the double or triple bond.
Naming branched chain alkanes substituent- atom or group of atoms that takes the place of hydrogen on a hydrocarbon molecule ex. C, O, N, S, P, Cl, F, I, Br
Alkyl Group hydrocarbon substituent alkane with one H removed drop the -ane ending and add -yl H H C CH 3 methyl H H H H C C CH 3 CH 2 ethyl H H
Name the following: 3,3-diethylhexane
Draw the following: 2,2,4-trimethylpentane
Draw the following: 3-ethyl-2-hexene
Draw the following: 4-bromo-2,2-dichloro-3,5- diethyl-6-fluorooctane
Properties of Hydrocarbons nonpolar not attracted to water
Structural Isomers compounds that have the same molecular formula but different molecular structures. physical and chemical properties differ Butane 2-methylpropane or isobutane CH 3 -CH 2 -CH 2 -CH 3 CH 3 CH 3 -CH-CH 3
Geometric Isomers Each of the carbons of the double bond must have at least one substituent. Ex. CH 3 CH=CHCH 3 has 2 geometric isomers because the double bond is not free to rotate. Bond angle (sp 2 ) is 120 o.
Stereoisomers Stereoisomerism is the arrangement of atoms in molecules whose connectivity remains the same but their arrangement in space is different in each isomer. The two main types of stereoisomerism are: cis-trans isomerism optical isomerism
Optical isomerism is a form of isomerism where the two different isomers are the same in every way except being non- superimposable mirror images of each other. Optical isomers are known as chiral molecules. A compound is chiral when it cannot be superimposed on its mirror image. The pair of mirror imaged non-superimposable compounds are known as enantiomers. Even though very similar still, different enantiomers of the same chiral drug can have very different pharmological effects, mainly because the proteins they bind to are also chiral. The two enantiomers of bromochlorofluoromethane 4 different groups attached to the carbon
Cyclic hydrocarbons compounds that contain a hydrocarbon ring general formula is: C n H 2n Cyclopropane Cyclobutane
Aliphatic compounds hydrocarbon compounds which do not contain rings
Arenes unsaturated cyclic hydrocarbons Benzene, C 6 H 6, is an arene. Benzene is a flat molecule with resonance.
Shorthand ways to draw benzene:
Aromatic compound any substance in which the bonding is like benzene A benzene ring used as a substituent on a hydrocarbon chain is called a phenyl group. Ex. methylbenzene (toluene)
Natural gas- 80% methane, 10% ethane, 4% propane, 2 % butane Petroleum = complex mixture of hydrocarbons Cracking= a controlled process by which hydrocarbons are broken down or rearranged into smaller, more useful molecules
Functional Group Chemically reactive part of an organic molecule Learn these functional groups R means the rest of the molecule (usually hydrocarbon
The Common Functional Groups ClassGeneral Formula HalohydrocarbonsR X AlcoholsR OH EthersR O R Aldehydes
The Common Functional Groups ClassGeneral Formula Ketones Carboxylic Acids Esters AminesR NH 2
Halocarbons Organic compounds containing F,Cl, Br, or I Halogen groups are named as substituents just as alkyl groups are. Cl I I Cl-C-Cl CH 3 -CH-CH-CH 3 H Cl-CH 2 -CH 3 CH 3 chloromethane Trichloromethane (chloroform) 2,3-diiodobutane 1-chloropropane bromobenzene
Alcohols Methanol Methyl alcohol “wood alcohol” Ethanol Ethyl alcohol “drinking alcohol” Organic compounds with a hydroxyl group (-OH) Naming: drop “e”, add “-ol”
Alcohols can be classified as primary, secondary or tertiary.
Properties of Alcohols Hydrogen bonding Short-chained alcohols are soluble in water Fermentation- production of ethanol from sugars by the action of yeast or bacteria C 6 H 12 O 6 2CH 3 CH 2 OH + 2CO 2 Denatured Alcohol- ethanol with an added substance to make it toxic
Ethers Compounds in which oxygen is bonded to two carbon groups R-O-R’ Name the R groups in alphabetical order and add the word ether. ethyl methyl ether dimethyl ether ethyl phenyl ether
diethyl ether 1 st reliable general anesthetic, 1842
Aldehydes Organic compounds in which the carbon of the carbonyl group ( C=O ) is always joined to at least one H. Naming: drop “e”, add “-al”, carbonyl carbon is #1
Ketones Organic compounds in which the carbon of the carbonyl group is joined to 2 other carbons. The carbonyl group is in the middle of the chain instead of the end of a chain as in an aldehyde. Naming: drop “e”, and “one”. If carbonyl can be in more than one position, give it a # Propanone (acetone) 3-hexanone
Naming: drop “e”, add “oic acid” The carboxyl carbon is always #1.
Esters Derivatives of carboxylic acids in which the –OH of the carboxyl group has been replaced by an –OR from an alcohol Formed by combination of a carboxylic acid with an alcohol in a dehydration reaction Often common flavors and odors Naming: Name alkyl group, then acid with –ate ending
methyl ethanoate or methyl acetate methyl methanoate or methyl formate ethyl ethanoate or ethyl acetate (apple scent)
Amines -NH 2 the suffix amine is added to the alkyl substituent can also be named as an amino group ethylamine cyclohexylamine 3-aminopropanoic acid
POLYMERS made of repeating units called monomers