Use the curved-arrow formalism to show how the electrons flow in the resonance form on the left

Use the curved-arrow formalism to show how the electrons...

Key Concepts

Mechanistic Steps

Mechanistic steps outline the individual electron movement and bond rearrangements that lead from the reactants to the products. Understanding these steps is essential for predicting reaction outcomes and for interpreting the pathway through which a molecule's resonance forms interconvert.

Curved-Arrow Formalism

This is a diagrammatic convention used in organic chemistry to illustrate the movement of electrons during a reaction. In this method, arrows indicate the direction of electron flow, with the tail of the arrow showing the origin of the electrons (such as a lone pair or pi bond) and the head showing where electrons are moving, guiding the understanding of how bonds are broken and formed.

Resonance

Resonance involves depicting a molecule by two or more contributing structures which together describe the delocalization of electrons. These structures do not represent distinct isomers but rather different distributions of electron density, and the true electronic structure is a hybrid of these representations.

Electron Flow

Electron flow refers to the movement of electrons from areas of high electron density to areas of lower electron density in a molecule, which is crucial for understanding how chemical reactions occur. It is important for mapping out the steps in a reaction mechanism, especially when using curved-arrow formalism.

Transcript

00:01 Hey guys, so in this question, we're given three compounds, and each of them were given resonant structures for.

00:07 And we're asked to denote with curved arrows the movement of electrons between these two structures.

00:14 So in part a, we're given this compound.

00:16 And we can see here that this oxygen right here has three lone pairs of electrons, and this sulfur right here has two lone pairs.

00:26 On the right resonance structure, we see that the electrons seem to move from the oxygen to this double bond and from this double bond connecting the sulfur to the sulfur right here, which now has three lone pairs of electrons and the formal charge of negative 1.

00:48 So to do this resident structure, the first thing i'm going to do is i'm going to move my electrons from my oxygen to.

00:57 This bond right here.

01:01 And i'm using a double -headed arrow to indicate a pair of electrons moving instead of half of arrow to show that one electron moves.

01:10 So when i do that, my electrons are going to move there, forming a double bond.

01:15 But now the carbon right here is going to have five bonds if this double bond forms.

01:20 And carbon cannot have five bonds because of its octet.

01:24 So when we do that we have to move electrons from this double bond to the sulfur.

01:34 And sulfur now is going to gain two electrons and doing our formal charge equation, we find that it now has the negative charge.

01:46 So double checking all of this, we can see that our net formal charge for the right matches that of the left, and the movement of electrons does check out, and everything has a complete octet.

01:57 So this is our resin structure diagram for part a...

Please give Ace some feedback