Draw the enol or keto tautomer(s) of each compound. |...

Name: Problem 1, Chapter 23: Organic Chemistry
Uploaded: 2019-12-24T19:10:13-08:00
Duration: 5 min 24 s
Channel: Ian Kaigh
Description: Draw the enol or keto tautomer(s) of each compound.

Key Concepts

Tautomerism

Tautomerism is a type of isomerism where compounds exist in a dynamic equilibrium between two forms that differ primarily in the placement of a proton and the arrangement of double bonds. This concept is key to understanding how a single molecular formula can represent distinct structures with different functional groups.

Keto Form

The keto form is one of the tautomers typically featuring a carbonyl group (C=O). This form is often more stable due to the strong carbon-oxygen double bond and is usually the predominant structure under normal conditions in many carbonyl compounds.

Enol Form

The enol form is the alternative tautomer characterized by the presence of an alkene (carbon-carbon double bond) adjacent to an alcohol group (OH). Although generally less stable than the keto form, the enol form is important in various reactions, such as electrophilic additions and some condensation reactions.

Keto-Enol Tautomerism

Keto-enol tautomerism involves the interconversion between the keto and enol forms of a compound. This process typically involves the migration of an alpha hydrogen and the shift of a double bond, and it plays a significant role in the reactivity and mechanism of many organic reactions, including those in biochemical pathways.

Transcript

00:02 This is the answer to chapter 23, problem number one from the smith organic chemistry textbook.

00:10 This problem asks us to draw the enol or keto totemir or totemers of each compound.

00:17 Okay, so for a, we're starting from an enol, so we're going to want to draw the keto totemir.

00:27 And so that is going to look like this.

00:32 So remember the double bond moves from being carbon carbon to being carbon oxygen.

00:40 And the oxygen loses a hydrogen and it goes to the carbon that is losing the double bond so that nothing is charged or anything.

00:49 Everything has its right number of protons.

00:56 Okay.

00:57 And so that's a.

00:58 So then for b, we're starting from an aldehyde, which is a keto form.

01:04 And so we're going to have to draw the enol totemir.

01:10 And so this time, instead of what we did in a, so we will take one of the double bonds from the carbon oxygen double bond.

01:24 We'll take one of the bonds from the carbon oxygen double bond, and we will move it so that it is a carbon carbon double bond instead, so that'll be right there.

01:33 And then we will put a proton on the oxygen to get an alcohol.

01:38 And so there is the enol form of b.

01:42 Okay, so for c, again, we're starting from a keto form.

01:48 So we're going to need to draw the enol.

01:50 And here there are actually going to be two possible enols.

01:54 So they will look like this.

02:02 So basically the two forms arise because we can put the double bond here, or we could put the double bond on the other side.

02:11 So there's one form, and then the other form would have the double bond there instead.

02:21 Okay, so that is c.

02:24 For d, we are starting from a keto form, and so we're going to draw the enol form.

02:32 Or no, i apologize.

02:34 I said that backwards.

02:35 We are starting from the enol form, and so we will draw the keto form here.

02:39 And so our double bond has moved so that it's now a carbon oxygen double bond.

02:47 And so that is d...

Please give Ace some feedback