Mechanism

Curly Arrow Cartoons

The actual curly arrow mechanisms are in a way themselves cartoons, how they map to the reality in the way that a Micky Mouse might map to real life.

Dramatic Emphasis

I have one slide where I'm first demonstrating how we use curly arrows and that shows an arrow going in a particular direction from a nucleophile to an electrophile and emphasising that the arrow shows electrons moving - so it's got to start from where they are.  There has to be some electrons there for them to move.  So the whole screen goes black and comes up with a little orange box of 'never do this' which is an arrow starting from an H+, which has no electrons. The dramatic emphasis that the whole room goes dark and then it's just up there.

Learning a New Language

You're learning a new language as well as new concepts. There's lots of vocab, so terms like electrophile and nucleophile and many others. So learning the language, learning the code that we use, the curly arrow code, and then starting to apply that in half a dozen or a dozen or so different contexts, different reactions.

Central Concepts

They struggle with the language of chemistry.  So we sort of need to teach them the process and how to work out how to do these things.  We know that their tendency is just to attempt to memorise reactions.  Whereas if we can teach them to derive … find out what the nucleophile and the electrophile is then all they have to do is draw a curly arrow from the nucleophile to the electrophile, rather than trying to work out what the reaction is itself. 

Reinforce Concept in Different Contexts

Keep coming back to the curly arrow concept, in terms of reinforcing it in different contexts. For a first-year course that’s about 20 lectures, introduce the curly arrow concept in lectures four to seven, then revisit it every lecture thereafter. For 13 or 14 lectures, it would come up in some different form - different examples, different ways of using it, referring back to the original concepts, reiterating the vocabulary, the language that's being used.

Re-Summarise

Repeat, re-summarise. Do not put the material on internet to make students write it down!

Practice Problems During Lecture

Try to encourage active learning in the lecture theatre. Talk about a concept and then ask them to look at some examples and work through them on their own.

Treat Mechanisms as Cartoons

The actual curly arrow mechanisms are in a way themselves cartoons, how they map to the reality in the way that a Micky Mouse might map to real life.

Identify Core Mechanism

There could be five “different” reactions, but actually they are the same core mechanism. If they can identify an electrophile and a nucleophile and how they get together in a particular context, then they understand all five of the reactions and another 55 too, if they choose to. The ultimate goal is that they have a skill-set, a set of tools, that allows them to meet any reaction, even reactions they have not seen before, and apply the concepts, use the tools, and get a handle on what is actually happening.

The Curly Arrow Code

They're learning a new language as well as new concepts. There's a lot of vocabulary - terms like electrophile and nucleophile and many others. So it’s about learning the language, learning the curly arrow code that we use, and then starting to apply that in half a dozen different contexts.

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