Alkene - Alkyne

C11-5-14 NAMING AND DRAWING Vocabulary & Concepts OUTCOME QUESTION(S): Name and draw structural models of simple and branched alkanes. Include: complete structural formula, molecular formula, general formula, isomers branched alkenes and alkynes. Compare and contrast the structure and uses of aromatic and aliphatic hydrocarbons. Vocabulary & Concepts

Remember what we know of double and triple bonds: Double bonds C = C H C H Triple bonds C H C ≡ C H Both considered unsaturated

Always show the double bond in the condensed formula Alkenes Suffix ene General formula – CnH2n Always show the double bond in the condensed formula Decene C10H20 Methene Ethene Propene Butene Pentene Hexene Heptene Octene Nonene Not possible… CH2=CH2 CH2=CHCH3 CH2=CHCH2CH3 CH2=CHCH2CH2CH3 CH2=CHCH2CH2CH2CH3 CH2=CHCH2CH2CH2CH2CH3 CH2=CHCH2CH2CH2CH2CH2CH3 C9H18 CnH2n n = 10 2n = 2(10) = 20

C C - C = C - C - C - C Naming Alkenes and Alkynes 5- methyl hex-2-ene Find the parent chain that has the double/triple bond. Find the location of the bond by numbering carbons from the end that gives the lowest number to the bond. Show the location of the bond with a hyphen in the parent name Branches named as per the rules for an alkane The double bond is the MOST important thing – number the carbons with that in mind C - C = C - C - C - C C 5- methyl hex-2-ene 1 6 2 5 4 3 3 4 2 5 6 1

Lowest number to the double bond Draw the structure of 4-methylpent-2-ene. C H3 C – C = C – C – C H3 H H H H3 1 2 3 4 5 Name the following structure. Lowest number to the double bond CH3CH2CH(CH3)CH=C(C2H5)CH2CH3 7 6 5 4 3 2 1 3- ethyl- 5- methyl hept-3-ene

Draw it out first if you need to… Draw a condensed formula for 2,5,5-trimethylhex-2-ene. Draw it out first if you need to… C H3 C H3 C – C = C – C – C – C H3 H H2 H3 1 2 3 4 5 6 C H3 CH3C(CH3)=CHCH2C(CH3)2CH3 1 2 3 4 5 6 2,5,5-trimethylhex-2-ene

Be careful when adding the hydrogens Alkynes Suffix yne General formula – CnH2n-2 Be careful when adding the hydrogens Decyne C10H18 Methyne Ethyne Propyne Butyne Pentyne Hexyne Heptyne Octyne Nonyne Not possible… CH≡CH CH≡CCH3 CH≡CCH2CH3 CH≡CCH2CH2CH3 CH≡CCH2CH2CH2CH3 CH≡CCH2CH2CH2CH2CH3 CH≡CCH2CH2CH2CH2CH2CH3 C9H16 CnH2n-2 n = 10 2n = 2(10)-2 = 18

2,2,5,5-tetramethylhex-3-yne Draw a structural of 2,2,5,5-tetramethyhex-3-yne. C H3 C H3 C – C – C ≡ C – C – C H3 H3 1 2 3 4 5 6 C C H3 H3 2,2,5,5-tetramethylhex-3-yne

If the location of the bond is not shown – assume it is off carbon #1 Like Alkyl groups (trimethyl), prefixes and numbers must be used to indicate multiple double or triple bonds. C = C – C = C Buta-1,3-diene 1 2 3 4 C ≡ C – C – C ≡ C C 3-methylpenta-1,4-diyne 1 2 3 4 5 If the location of the bond is not shown – assume it is off carbon #1

This is messed up…just showing the possibilities (fun, right?) Name the condensed formula below: HC≡CC=(C2H5)C=CH(CH3)CH(CH3)CH3 1 2 3 4 5 6 7 C H3 H2 C H3 H C ≡ C – C = C = C – C – C H H3 1 2 3 4 5 6 7 C H3 3- ethyl- 5,6- dimethyl hept-3,4-dien-1-yne This is messed up…just showing the possibilities (fun, right?)

C11-5-14 NAMING AND DRAWING Vocabulary & Concepts CAN YOU / HAVE YOU? Name and draw structural models of simple and branched alkanes. Include: complete structural formula, molecular formula, general formula, isomers branched alkenes and alkynes. Compare and contrast the structure and uses of aromatic and aliphatic hydrocarbons. Vocabulary & Concepts