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Organic Chemistry. Organic Chemistry: the study of carbon containing compounds. Prior to 1828 , organic compounds can only be obtained from living organism until Fredrick Wohler prepared urea - chemical in urine (an organic compound) NH 4 Cl + AgNCO → NH 2 -CO-NH 2 + Ag
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Organic Chemistry Organic Chemistry: the study of carbon containing compounds. • Prior to 1828, organic compounds can only be obtained from living organism until Fredrick Wohler prepared urea - chemical in urine (an organic compound) • NH4Cl + AgNCO → NH2-CO-NH2 + Ag • Now - the bulk of organic compounds are manufactured in the lab. Clothes perfumes shoes athletic products foods Makeup furniture computers televisions cars Plastics CD dishes cups carpets linoleum etc
EXCEPTIONS • Inorganic compounds: containing carbon atoms Oxides / like CO and CO2 are inorganic examples Cyanides / like NaCN Mg(CN)2 are inorganic compounds Carbonates /like Na2CO3 MgCO3 are inorganic compounds Carbides / like SiC Al4C3are inorganic compounds
BOND CAPACITY OF ATOMS O H Cl Br F N C HYDROCARBONS GROUPS OF ORGANIC COMPOUNDS CONTAINING HYDROGEN AND CARBON H C O N F Cl Br I ALIPHATICS AROMATICS Have distinct cyclic carbon ring Alkanes Alkenes Alkynes Are not named for their Aroma Cyclic compounds
HYDROCARBONS • ALIPHATICS AROMATICS CONTAIN BENZENE RING ALKANES ALKYNES ALKENES DOUBLE BONDS SINGLE BONDS TRIPLE BONDS CNH2N-2 CNH2N CNH2N+2 N – REPRESENTS C ATOMS COLORLESS,FLAMMABLE LIQUID SWEET AROMA CYCLIC COMPOUNDS CARCINOGENIC EFFECT AROMATICS MEAN THAT - CONJUGATED RINGS OF CARBON - UNSATURATED BONDS OF C - RESONANT BONDS OF CARBON
I. Classes of Organic Compounds Hydrocarbons (C & H only) Heteroatomic compounds Alcohols * Aliphatic Aromatic * Alkanes * ethers aldehydes Alkenes * benzene ring ketones Carboxylic acids * Alkynes * Esters * amines Cyclic compounds * amides
What is the general formula of alkanes? (CnH2n + 2)
BRANCHES - OFF PARENT CHAIN • ALL WILL APPEAR TO HAVE C AND H THE BRANCHES WILL HAVE ONE LESS HYDROGEN AND ARE CALLED ALKYLS ALKYL FORMULA CONDENSED STRUCTURAL PREFIX - C METH - 1 ETH - 2 PROP - 3 BUT - 4 PENT - 5 HEX - 6 HEPT - 7 OCT - 8 NON - 9 DEC - 10 METHYL - CH3 ETHYL - C2H5 PROPYL - C3H7 BUTYL - C4H9 PENTYL - C5H11 HEXYL - C6H13 HEPTYL - C7H15 AND SO ON !! CH3 CH3-CH2 CH3-CH2-CH2 CH3-CH2-CH2-CH2 CH3-CH2-CH2-CH2-CH2 CH3-CH2-CH2-CH2-CH2-CH2 CH3-CH2-CH2-CH2-CH2-CH2-CH2 AND SO ON !!!!
Alkyl Groups • H • H C CH3 methyl • H • H H • H C C CH3-CH2ethyl • H H Branches off parent chain Not part of the parent chain in a sequence
Ways of presenting organic compounds • Molecular formula - indicate type and number of atoms C3H8 • Structure formula - shows connectivity of atoms in a compound • Condensed structural formula - shows connecting group of atoms in a compound • CH3 - CH2 -CH3 Line structural - shows hydrocarbons as lines with bends for carbon
Branched Alkanes • CH3 • CH3-CH-CH3 • methyl groups • CH3CH3 • CH3-CH-CH-CH3 Ethyl group CH2CH3 CH3-CH2-CH2-CH-CH2-CH3 BRANCHES ARE NOT PART OF THE PARENT CHAIN !
Nomenclature • 1. Find the longest continuous chain of carbon atoms. Assign this chain as the parent name .(# of carbon atoms) • 2. Determine the groups attached to the parent chain • 3. Assign attachment position of group to main chain by starting at end which gives lowest position number. • 4. Identical groups attached to the main chain are designated with prefixes. • 2-di, 3-tri, 4-tetra, 5-penta • 5. Different groups attached to main chain are written in alphabetical order.
Nomenclature • CH3(branch) • CH3-CH2-CH2-CH-CH2-CH3 (parent chain) • 6 5 4 3 2 1 • 3-methylhexane • on third C CH3 six carbons (hex) NUMBER FROM RIGHT TO LEFT – BRANCH CLOSEST TO THE RIGHT SIDE !! CARBON NUMBER BRANCH PARENT CHAIN
NOMENCLATURE OF ALKANES • 1.CARBON NUMBER OF BRANCH IS FIRST 2. THERE MAY BE SIMILAR BRANCHES – PLACE ALL CARBON NUMBERS IN ORDER. Eg 2,2,3 - 3,4,5 - separated by commas followed by a hyphen 3. THE NAME OF THE BRANCHES MUST FOLLOW – IF THERE ARE MULTIPLE BRANCHES YOU MUST ADD PRFIXES TO INDICATE HOW MANY… 2-DI 3 -TRI 4 -TETRA 5 - PENTA 6 - HEXA 4.THERE MAY BE DIFFERENT BRANCHES SO YOU MAY HAVE DIFFERENT ALKYL GROUPS AND CARBON NUMBERS… 3,3-diethyl-2,5,5-trimethyl (write down groups alphabetically – ignore prefix) 5.THE NAME OF THE PARENT CHAIN COMES LAST – ONE WORD 3,3- diethyl-2,5,5- trimethyloctane EASY !!
Nomenclature • A. CH3CH3 • CH3CHCH2CHCH3 • B. CH3 CH3 • CH3CH2CHCH2CCH2CH3 • CH3 2,4-dimethylpentane 3,3,5-trimethylheptane
Nomenclature • Write a condensed structure for • A. 3,4-dimethylheptane • B. 2,2-dimethyloctane
Solution • A. 3,4-dimethylheptane CH3 • CH3CH2CHCHCH2CH2CH3 • CH3 • 2,2-dimethyloctane CH3 • CH3CCH2CH2CH2CH2CH2CH3 • CH3 Quiz
Haloalkanes • An alkane in which one or more H atoms is replaced with a halogen (F, Cl, Br, or I) • CH3Br 1-bromomethane • Br • CH3CH2CHCH3 2-bromobutane • Cl • chlorocyclobutane
Haloalkanes • List other attached atoms or group in alphabetical order. • Br = bromo, Cl = chloro • Cl Br • CH3CHCH2CHCH2CH2CH3 • 4-bromo-2-chloroheptane
Learning Check • The name of this compound is: • Cl CH3 • CH3CH2CHCH2CHCH3 • 1) 2,4-dimethylhexane • 2) 3-chloro-5-methylhexane • 3) 4-chloro-2-methylhexane
Learning Check dichloromethane triodomethane tetrabromomethane dichlorodifluoromethane
Learning Check bromomethane 2-chloropropane iodocyclohexane 2-bromo-2,4-dimethylpentane
Saturated and Unsaturated Compounds • Saturated compounds (alkanes) have the maximum number of hydrogen atoms attached to each carbon atom. • Unsaturated compounds have fewer hydrogen atoms attached to the carbon chain than alkanes. • Unsaturated compounds contain double or triple bonds
Alkenes and Alkynes • Alkene (CnH2n) • 1. - ene suffix for alkenes • 2. Main chain must include the double bond. • 3. position of double bond indicated by prefix numbering location. • 4. For multiple double bonds : • di = 2 double bonds • tri = 3 double bonds • Alkyne (CnH2n-2) • 1. - yne suffix for alkynes • 2. Nomenclature rules are similar to that • of alkenes
Alkenes and Alkynes • When the carbon chain has 4 or more C atoms, number the chain to give the lowest number to the double or triple bond. • CH2=CHCH2CH31-butene • CH3CH=CHCH32-butene • CH3CCCH32-butyne
Learning Check • Write the IUPAC name for each of the following unsaturated compounds: • A. CH3CH2CCCH3 • CH3 • B. CH3C=CHCH3 2-pentyne 2-methyl-2-butene
Cycloalkanes • same general formula as alkenes • structural isomers of alkenes
Learning Check • Name the following: bromocyclopentane 1,3-dichlorocyclohexane
Learning Check 5-bromo-2-methylheptane 4-fluoro-1,2-dimethylcyclohexane 1,2,6-trichloro-4-ethyl-2-methylheptane
Isomers Same molecular formula Same number and types of atoms Different arrangement of atoms
Isomers • The formula C4H10 has two different structures • CH3 • CH3CH2CH2CH3 CH3CHCH3 • butane 2-methylpropane • When a CH3 is used to form a branch, it makes a new isomer of C4H10.
Learning Check • CH3CH2CH2CH2CH3 pentane • CH3 • CH3CHCH2CH3 2-methylbutane • CH3 • CH3CCH3 2,2-dimethylpropane • CH3 Write 3 isomers of C5H12 and name each.
Learning Check Draw all of the constitutional isomers for the following. C4H9Cl 2-chloro-2-methylpropane 1-chlorobutane 2-chlorobutane 1-chloro-2-methylpropane
Aromatics • unsaturated cyclic hydrocarbons
Aromatics • 1. Monosubstituted • a. group benzene • chlorobenzene ethylbenzene • b. special names: • phenol • 2. Benzene as a group • - phenyl
Alcohols A carbon compound that contain -OH (hydroxyl) group • CH4 methane • CH3OH methanol • CH3CH3 ethane • CH3CH2OH ethanol
Alcohols IUPAC names for longer chains number the chain from the end nearest the -OH group. • CH3CH2CH2OH 1-propanol • OH • CH3CHCH32-propanol • CH3 OH • CH3CHCH2CH2CHCH35-methyl-2-hexanol
Functional Groups • Part of an organic molecule where chemical reactions take place. • Composed of an atom or group of atoms. • Replace a H in the corresponding alkane. • Provide a way to classify organic compounds.
Ethers • Contain an -O- between two carbon groups • CH3-O-CH3 dimethyl ether • CH3-O-CH2CH3 ethyl methyl ether
Learning Check • Classify each as an alcohol (1), phenol (2), or an ether (3): • A. _____ CH3CH2-O-CH3C. _____ CH3CH2OH • B. _____ 3 1 2
O CH3CH2CH2C H O CH3CH2CCH2CH3 Functional Groups aldehyde ketone
Aldehydes and Ketones In an aldehyde, an H atom is attached to a carbonyl group O carbonyl group CH3-C-H In a ketone, two carbon groups are attached to a carbonyl group • O carbonyl group • • CH3-C-CH3
Naming Ketones OO • • CH3 -C-CH3 CH3-C-CH2-CH3 • propanone 2-butanone
Learning Check • Classify each as an aldehyde (1), ketone (2) or neither(3). • O • • A. CH3CH2CCH3 B. CH3-O-CH3 • CH3 O • • C. CH3-C-CH2CH D. • CH3 3 2 2 1
CH3 O CH3CHCH2C OH O CH3CH2C OCH2CH3 Functional Groups carboxylic acid ester
Functional groups alcohol alkene ester ketone carboxylic acid
carboxylic acid ester ether aldehyde amine