Organic Nomenclature Alkanes SWBAT: Name alkanes with alkyl groups

Organic Chemistry The study of the structure, properties, composition, reactions, and preparation (synthesis) of carbon-based compounds, hydrocarbons and their derivatives

Organic Molecules Organic molecules are compounds consisting of nonmetals (hydrogen, nitrogen, oxygen, the halogens, phosphorus, silicon and sulfur) with carbon Due to carbon’s hybrid bonding orbitals, organic molecules have a variety of configurations The types of atoms bonded to the carbon atoms will ultimately determine function and properties of the compound

Organic vs. Inorganic General Comparison Organic Compounds Inorganic Compounds Mostly covalent bonding Low boiling pt Low melting pt High flammability Most are nonpolar Not soluble in water unless a polar group is present Do not conduct electricity Many ionic, some covalent High boiling pt High melting pt Low flammability Most are ionic or polar covalent Most are soluble in water unless nonpolar Conduct electricity

Hydrocarbons A hydrocarbon chain is a series of carbons bonded together with numerous hydrogen's attached Includes Alkanes, Alkenes, Alkynes and Cyclical HC Use certain prefixes for naming to indicate chain length

Alkane Formulas and Names Strings, branches of carbons with single bonds between C Essentially many CH4 reacted together Formula rules: CnHn+2 CH2 – methylene unit Names: Prefixes indicate # of C followed by -ane

Homologous series of the first 12 linear alkanes Methane (meth=1) CH4 Ethane (eth =2) C2H6 Propane (prop=3) C3H8 Butane (but=4) C4H10 Pentane (pent=5) C5H12 Hexane (hex=6) C6H14 Heptane (hept=7) C7H16 Octane (oct=8) C8H18 Nonane (non=9) C9H20 Decane (dec=10) C10H22 Undecane (undec = 11) C11H24 Dodecane (dodec= 12) C12H26

1-10 Alkane Prefix Quiz Just the prefix…not the -ane CH4 C6H14 C2H6 C7H16 C3H8 C8H18 C4H10 C9H20 C5H12 C10H22

Mnemonic for First Four Prefixes Meth- Monkeys Eth- Eat Prop- Peeled But- Bananas

Mnemonic for First 8 Prefixes Mrs. Edwards Plays Basketball, Please Hold Her Overcoat Methane CH4 Ethane C2H6 Propane C3H8 Butane C4H10 Pentane C5H12  Hexane C6H14 Heptane C7H16 Octane C8H18           

Alkane Naming and Drawing Expanded structure 1. Make string of carbons (prefix= # of C) Ex: Butane (but=4)

Butane 2. Condensed structure A CH3-CH2-CH2-CH3 3. Condensed structure B CH3CH2CH2CH3 4. Condensed structure C CH3(CH2)2CH3

Butane 5. Carbon skeleton: C-C-C-C *all H are understood 6. Kekulé or Line-angle formula (most reduced form) Each endpoint, every corner symbolizes a C H are understood

Alkanes methane CH4 hexane C6H14 ethane C2H6 heptane C7H16 propane octane C8H18 butane C4H10 nonane C9H20 pentane C5H12 decane C10H22

Alkyl Groups Substituent – element or group of elements that branch off parent chain (replace a H) methyl group ethyl group propyl group

Alkyl Groups isopropyl butyl groups butyl secbutyl tertbutyl isobutyl Only iso- is alphabetized, tert, sec are not.

Haloalkanes Haloalkanes have a halogen that has replaced a hydrogen The halogens are substituent groups treated the same as the alkyl groups. Alpha without prefixes F = fluoro Cl = chloro Br = bromo I = iodo

Rules to Naming Hydrocarbon Chains Number the longest continuous chain of carbons Carbons attached to double/triple bonds receive the smallest number possible If no double/triple bonds are present, carbons with groups attached, receive the smallest number possible Use prefixes for repeating groups di, tri, tetra, penta, hexa, …. Alphabetize groups without prefixes All lowercase, commas between numbers, dashes between numbers and words Use appropriate ending ane, ene, yne or functional group ending

Find The Longest Continuous Chain of Carbons

Number the Carbons so that the groups receive the smallest number possible

Use prefixes with same multiple substituent groups 7 – ethyl – 3,5 - dimethyl – 6 - tertbutylundecane

Naming Hydrocarbon Chains

Naming Hydrocarbon Chains

Naming Hydrocarbon Chains

If more than one type of substituent group, alpha If more than one type of substituent group, alpha. the groups without prefixes 5 – secbutyl - 3,6 – dimethylnonane 4 – tertbutyl - 5 - ethylnonane

Cycloalkanes 1. Start at noon and go clockwise until you get to first carbon with a substituent group this is # 1 2. Go clockwise or counterclockwise so substituent groups receive the smallest number possible

Cyclical Alkanes have 2 H less from ring closure cyclopropane C3H6 cyclooctane C8H16 cyclobutane C4H8 cyclononane C9H18

Alkanes cyclodecane C10H20 cycloundecane C11H22 cyclododecane C12H24

Practice methylcyclopentane 1,1-dimethylcyclopentane

Practice 1,2-dimethylcyclopentane 1,3-dimethylcyclopentane

Practice 2-ethyl,1-methylcyclohexane

Practice 2-cyclopropyl-4-ethyl-1-methylcyclohexane