Rules of the Day 320N

1. Alkyllithium reagents are the most basic limiting their use, Grignard reagents will deprotonate anything more acidic than an alcohol and Gilman reagents are the least basic, allowing them to react with primary haloalkanes, vinyl halides and aryl halides to make C-C bonds. Click here to watch a video that explains Gilman reagents in more detail.

2. When doing synthesis problems you need to count carbons in the starting materials and products (to figure out if new C-C bonds are formed and if so, where), work backwards (start by determining what was the last reaction used to make the product, then continue going backwards until you connect to the starting materials) and use your Key Recognition Elements (KREs) to identify important structural features of the products that reveal what reactions were used to create them.

3. You are responsible for learning the nomenclature of aldehydes and ketones. Refer to Section 16.2

4. The most important feature of carbonyl groups is that the carbon-oxygen double bond is highly polarized, with a partial positive charge on the carbon atom and a partial negative charge on the more electronegative oxygen atom. From this description alone it is clear that nucleophiles will attack the carbon carbon atom (while C=O pi bond breaks) and Lewis acids or protons will react with the carbonyl oxygen atom. Time capsule: Strong base can remove a hydrogen on carbon atoms adjacent to carbonyl groups to give enolates.

5. The reactions of carbonyl compounds with nucleophiles occur according to four basic mechanism, we will call Mechanism A - D. The differences depend on when or if protons bond to the oxygen atom, and whether there is a leaving group attached to the carbonyl group.

6. Grignard reagents add to aldehydes and ketones to give tetrahedral alkoxide intermediates (can be isolated). These alkoxides are protonated when the chemist opens the flask and adds acid to give alcohols. Mechanism A. Carbon-carbon bond forming!

Homework:

Read: Sections 16.5, 16.6, 16.10 and 16.11 in the ebook textbook (skip 16.7-16.9 for now). This text is part of the Longhorn Textbook access program.

Take the Daily Quiz 3 before 10 PM tomorrow. Click here to access the quiz. These quizzes are designed to review the important material from today's lecture. Together, they will count as 3% of your final grade.

Start working on the Homework Problem Set 2, due at 10 PM on Monday, Juanuary 29. Click here to access the Homework Problem Set 2. Note there are Aktiv Learning and Gradescope Questions, and you MUST DO BOTH. Homeworks will be worth 10% of your final grade (20% from the Aktiv Learning and 80% from the Gradescope portions of the homework.

Click here for directions for how to use Gradescope

Click here to get started with Aktiv Learning