Schedule Today (4/17): Chapter 21 Friday (4/19): Chapter 21 Should have read through at least Section 21.4 Friday (4/19): Chapter 21 Read through at least 21.5 Review Sessions: Monday (4/22): 203 Noyes Lab, 8-10 pm Tuesday (4/23): 101 Armory, 4-6 pm

Alkenes and Alkynes These are called “unsaturated hydrocarbons” Double bonds = alkene Triple bonds = alkyne Alkenes: CnH2n Akynes: CnH2n–2 Cis-trans isomerism

Alkenes – ethene and propene Ethene (ethylene) Propene (propylene)

Alkenes – “butene” 1-butene IUPAC: But-1-ene a) cis-2-butene b) trans-2-butene

Aromatic Hydrocarbons Note: “phenyl” prefix versus “benzene” suffix. “Phenyl” is used when benzene is a substituent.

Clicker Question Name this compound. a) 3-methyl-4-hexene b) 3-methyl-trans-4-hexene c) 3-methyl-trans-3-hexene d) 4-methyl-trans-2-hexene e) trans-2-isoheptane

Clicker Question Name this compound. a) 3-methyl-cyclopentene b) 1-methyl-cyclo-3-pentene c) 4-methyl-cyclopentene d) cyclo-4-hexene e) 1-methyl-cyclopentene

Alkenes and Alkynes Double (and triple) bonds take preference over alkyl groups. trans-4-methyl-2-pentene (not trans-2-methyl-3-pentene)

Organic Chemistry “Humor”

Organic Chemistry “Humor” But keep triene!

Organic Chemistry “Humor”

Organic Chemistry “Humor” Name this molecule.

Organic Chemistry “Humor” Name this molecule.

Organic Chemistry “Humor” Name this molecule.

Organic Chemistry “Humor” Name this molecule.

Organic Chemistry “Humor” Name this molecule.

Organic Chemistry “Humor” Name this molecule.

Clicker Question How many isomers of “chlorobutane” are there? a) 1 b) 2 c) 3 d) 4 e) 5

Question How many isomers of “dichlorobutane” are there? Name them.

Alcohols (1°, 2°, and 3°) We label these based on the number of carbons attached to the carbon that is attached to the –OH group.

Clicker question Name the following compound. a) 7-methyl-2-propyl-5-octanol b) 4,9,-dimethyl-7-decanol c) 2,7,-dimethyl-4-decanol d) 2-methyl-7-propyl-4-octanol e) I get a different name/I cannot name this one

Ethers These are like alcohols (R-O-H vs. R-O-R’). Ether Boiling Pt. Boiling Point Dimethyl ether CH3-O-CH3 –25°C Ethanol CH3CH2OH 79°C Ethyl methyl ether CH3-O-CH2CH3 11°C Propanol CH3CH2CH2OH 82°C Diethyl ether CH3CH2-O-CH2CH3 35°C Butanol CH3CH2CH2CH2OH 117°C

Aldehydes and Ketones Similar to alcohols vs. ethers, the aldehydes and ketones have a similar structure (carbonyl group). This group is bonded to two carbons in ketones and at least one hydrogen in aldehydes.

Aldehydes – named with “-al” Methanal Methanaldehyde Formaldehyde

Ketones – named with “-one” 2-propanone Propanone Dimethyl ketone IUPAC? Propan-2-one Acetone