Now that pretty much the entire course has been covered, maybe it’s helpful to go back and highlight some of the key skills you should have in your toolbox as you finish up.
As I tell my students, there’s an infinite number of things to learn, but a finite number of important things to learn. Here’s my top 10.
- Be able to identify the electron-rich and electron poor atoms in a molecule, using electronegativity and resonance.
- Be able to draw resonance structures, using the “three legal moves“.
- Be able to draw curved reaction arrows
- Recognize when molecules are aromatic (and when they’re not)
- Be able to draw a general mechanism for electrophilic aromatic substitution. They all follow the same essential pattern.
- Carbonyl carbons are key electrophiles. Be able to draw their two key mechanisms: addition and elimination.
- Mechanisms (especially in carbonyl chemistry) can be broken down into their components. Learn how to condense and summarize the mechanisms so you don’t get overwhelmed. Example: PAPED.
- For each reaction you learn, be able to identify the bonds that form and the bonds that break.
- For each reaction you learn, if you’re given the products, be able to work backwards to determine what the reactants are.
- Mechanism problems: Make a detailed list of bonds that form and break. Think of this as your “to-do” list. Your mechanism will have to account for every item on the list. If you’re stuck, start by looking for the most electron-rich atom. This will be your nucleophile: your first curved arrow will usually start here.
- Synthesis: There are three questions to ask. Ask yourself 1) What’s new? What bonds have formed/broken here? What atoms are new? What atoms have disappeared? 2) What reactions do I know that could form/break these bonds? 3) In what order would this best occur?OK, so that was actually 11. Although this seems like a lot – and let’s face it, it is – focusing on doing each of these things well can really pay off in terms of increased efficiency in studying. I don’t know how many times I’ve had my students tell me what a lifesaver PAPED is, for instance.
If you’re stuck, or don’t know where to start, this list is a good place to begin.