Schedule Today (4/22): Chapter 21 Wednesday (4/24): Review for Exam 3 Any questions? Wednesday (4/24): Review for Exam 3 Friday (4/26): Discuss Exam 3 Monday (4/29): Semester Review Wednesday (5/1): Extended office hours

Exam III Thursday, April 25, 7:00-9:00 pm; rooms are on the website. Conflict: (4/25) 4:30-6:30pm in 329 Davenport; sign up in 1026 CA Conflict with conflict? Email me right away. Review sessions: Tonight (4/22): 217 Noyes Lab, 8-10 pm Tomorrow (4/23): 101 Armory, 4-6 pm Practice Exam is posted.

CH2=CH2 + H2O → CH3CH2OH (acid catalysis) Reactions of Alkenes CH2=CH2 + H2O → CH3CH2OH (acid catalysis)

Clicker question Which of the following alkenes will react with water to make a tertiary alcohol? a) ethene b) 1-butene c) 2-methylpropene d) 3-methyl-1-pentene e) 4,4-dimethyl-2-hexene

Reactions of Alcohols Primary alcohols can be oxidized to form aldehydes and then carboxylic acids. Secondary alcohols can be oxidized to form ketones Tertiary alcohols cannot be oxidized to form aldehydes or ketones. Why not?

Reactions of Alcohols One potential mechanism for the reaction:

Reactions of Alcohols If H2CrO4 is used as an oxidizer, HCrO3– is a product. Why? How many moles of electrons are gained by every one mole of H2CrO4? a) 1 b) 2 c) 4 d) 6 e) Not sure

Reactions of Alcohols If H2CrO4 is used as an oxidizer, HCrO3– is a product. Why? What is the oxidation state of carbon in the alcohol and the oxidation state of carbon in the aldehyde? a) 1, 2 b) 2, 1 c) –1, –2 d) –2, –1 e) Not sure

Reactions of Alcohols If H2CrO4 is used as an oxidizer, HCrO3– is a product. Why? What is the oxidation state of carbon in the alcohol and the oxidation state of carbon in the ketone?

Esterification Reaction of an alcohol and a carboxylic acid results in an ester. Note that water is a product.

Esters Also oil of wintergreen!

SN1 Mechanism Substitution Nucleophilic 1(Unimolecular) Occurs in two steps. Note that two products are possible.

SN2 Mechanism Substitution Nucleophilic 2(Bimolecular) Occurs in one step. Note that the product molecule is inverted.

Polymers – many parts (repeating)

Polymers – Addition Polymerization

Polymers – Addition Mechanism Note the formation of a free radical.

Polymers – Addition Mechanism 1. 2.

Polymers - Condensation A common form of nylon. Nylon is a called a copolymer because the two parts are different.

Polymers – Slime!

Clicker Question Name the following molecule. a) cis-2-methyl-4-heptene b) cis-6-methyl-3-heptene c) cis-1-isopropyl-3-pentene d) cis-1,1-dimethyl-3-hexene e) I cannot get this one.

Clicker Question How many of the following compounds are impossible? 3-methyl-2-pentyne 3-bromo-2-pentanone 3,3-dimethyl-2-heptene 1-bromo-2-butene a) 0 b) 1 c) 2 d) 3 e) 4