Organic Chemistry Organic Chemistry: The chemistry of carbon and carbon-based compounds Organic Chemistry in everyday life: Smells & tastes: fruits, chocolate, fish, mint Medications: Aspirin, Tylenol, Decongestants, Sedatives Addictive substances: Caffeine, Nicotine, Alcohol, Narcotics Hormones/Neurotransmitters: Adrenaline, Epinephrine Food/Nutrients: Carbohydrates, Protein, Fat, Vitamins Genetics: DNA, RNA Consumer products: Plastics, Nylon, Rayon, Polyester

Big Idea in Organic Chemistry Structure controls Function Each functional group has predictable reactivity

Drawing Organic Structures Shortcuts make structures easier & faster to draw Butane: C4H10 Lewis Structure Carbon Atoms Line Structure Only shows bonds C atoms assumed at each end and intersection of bonds H atoms not shown Assume 4 bonds to each C Fulfill C’s 4 bonds by adding H’s Condensed Structures CH3CH2CH2CH3 CH3(CH2)2CH3

Types of Organic Compounds Classified according to functional group Alkane Alkene Alkyne Haloalkane Alcohol Ether Ketone Aldehyde Carboxylic acid Amine Amino acid Amide

Names of Linear Alkanes and Alkyl Substituents C atoms Alkane Alkyl substituents 1 2 3 4 5 6 7 8 9 10 CH4 CH3CH3 CH3CH2CH3 CH3CH2CH2CH3 methane ethane propane butane pentane hexane heptane octane nonane decane -CH3 -CH2CH3 -CH2CH2CH3 methyl ethyl propyl etc. Root: number of C atoms Suffix: functional group (-ane for alkanes) (-yl for alkyl groups)

H C C H Methane CH4 Butane C4H10 H C ? C H ? R R Methyl -CH3 Butyl -C4H9 Where R = any other C atom or arrangement of C atoms

Common Names of other Alkyl Substituents Remember that R = any carbon chain R 3 carbons R isopropyl alphabetized as “i” “iso” indicates symmetry R R isobutyl alphabetized as “i” 4 carbons 2o R R 2o sec-butyl alphabetized as “b” Secondary carbon R 3o 3o R tert-butyl alphabetized as “b” Tertiary carbon

Naming Practice C H 2 - methylbutane butane Expanded Structure Line Structure H C 2 - methylbutane butane

Naming Practice H H CH3 H C C C H H C H H C H H C H H 4,4-dimethyl Line Structure 1 2 3 4 5 6 1 2 3 4 5 6 H H C H H C H H C H H 4,4-dimethyl hexane 3,3-dimethyl hexane Lowest sum of numbers is correct

Hydrocarbons Number of Carbon Atoms Alkanes CnH2n + 2 Alkenes CnH2n Alkynes CnH2n-2 1 2 3 4 5 6 7 8 9 10 Methane Ethane Propane Butane Pentane Hexane Heptane Octane Nonane Decane CH4 C2H6 C3H8 C4H10 C5H12 C6H14 C7H16 C8H18 C9H20 C10H22 ____ C2H4 C3H6 C4H8 C5H10 C6H12 C7H14 C8H16 C9H18 C10H20 _______ Ethene Propene Butene Pentene Hexene Heptene Octene Nonene Decene _______ Ethyne Propyne Butyne Pentyne Hexyne Heptyne Octyne Nonyne Decyne ____ C2H2 C3H4 C4H6 C5H8 C6H10 C7H12 C8H14 C9H16 C10H18

Alcohols (R-OH) R = -CH3 ‘methyl’ R = -CH2CH3 ‘ethyl’ Methanol (methyl alcohol) Ethanol (ethyl alcohol) R = -CH3 ‘methyl’ R = -CH2CH3 ‘ethyl’ Timberlake, Chemistry 7th Edition, page 437

Primary, Secondary, Tertiary Alcohols Primary (1o) Alcohol Secondary (2o) Alcohol Tertiary (3o) Alcohol Carbon attached to OH group R1 OH H C R1 OH H R2 C R1 OH R3 R2 C Alkyl group Examples: CH3 OH H C CH3 OH H C CH3 OH C 1o 2o 3o (One alkyl group) (Two alkyl groups) (Three alkyl groups)

Aldehydes and Ketones O Aldehyde R-C-H Ketone R-C-R' O Acetaldehyde (CH3CH) ethanal, ethyl aldehyde O Formaldehyde (CH2O) methanal Acetone (CH3COCH3) dimethyl ketone, 2-propanone Timberlake, Chemistry 7th Edition, page 453

Dimethyl Ether Dimethyl ether C2H6O Flammable anesthesia Timberlake, Chemistry 7th Edition, page 446

R- Functional Groups -CH3 methyl -CH2CH2CH2CH3 butyl CH3CHCH2CH3 H sec-butyl -CH2CH3 ethyl – CH2 – C – CH3 H CH3 isobutyl -CH2CH2CH3 propyl CH3CCH3 H isopropyl – C – CH3 CH3 tert-butyl

Alkenes and Alkynes Alkene Alkynes Double bonds Triple bonds ethene A ball-and-stick model of ethene C2H4, the simplest alkene. ethyne (acetylene) A ball-and-stick model of acetylene (IUPAC name ethyne) Timberlake, Chemistry 7th Edition, page 409

Aliphatic Hydrocarbons Alkane Alkene Alkyne Alkadiene General formula CnH2n + 2 CnH2n CnH2n - 2 CnH2n - 2 Typical structural formula – C – C – C – C – – C = C – C – C – – C = C – C – C – – C = C – C = C – butane 1-butene 1-butyne 1,3-butadiene Carbon-carbon bond type all single bonds one double bond one triple bond two double bonds Naming suffix -ane -ene -yne -diene

Cycloalkanes Formula CnH2n Cyclopropane Cyclobutane Cyclopentane Condensed Structural Formula Geometric Formula Formula CnH2n Name Cyclopropane Cyclobutane Cyclopentane Cyclohexane Timberlake, Chemistry 7th Edition, page 388

Benzene An Aromatic Compound C6H6 Resonance structures Kekule’s dream