Acyl Chlorides and Acid Anhydrides

making acyl chlorides from carboxylic acids we need to add moelcles to carboxylic acids suc as SOCl2 (sulphur dichloride)

Sulfur’s oxidation state in SOCl2 is…

4

Ethanoic acid and sulfurous dichloride react to form an acyl chloride, sulfur dioxide and hydrogen chloride.

Sulfur dioxide and hydrogen chloride are both gases.

This reaction is therefore…

reversible

non-reversible

B

(as the gaseous products escape into atmosphere)

as the reactants are both liquids and the prodcuts are both gasses, we can be sure to entropy ………………. whcih expalins why the reaction proceeds

increases

Give the equation for the reaction between ethanoic acid and sulfurous dichloride.

Give your answer using the structural formulas and do not include state symbols

CH_3COOH + SOCl_2 → CH_3COCl + SO_2 + HCl

What is the shape of sulfurous dichloride (SOCl2)?

What are the bond angles, according to VSEPR?

• trigonal pyramidal

• 107.

The root of this molecule’s name is…

eth-

(as acyl chlorides are the highest priority functional group so they say the suffix )

name this molecules

ethanoyl chloride

What acyl chloride is produced by the reaction between sulfurous dichloride and butanoic acid?

butanyl chloride

butanoic chloride

butoyl chloride

butanoyl chloride

D

Name the acyl chloride derived from propanoic acid?

propanoyl chloride

Name all the products of the reaction between pentanoic acid and sulfurous iodide.

pentanoyl chloride , sulphur dioxide, hydrogen iodide

What is the IUPAC name of this molecule?

heptanoyl chloride

To name an acyl chloride, count the number of carbons in the main chain to work out the root.

Then, add the suffix…

anoyl chloride

This is called…

propanoic anhydride

Acid anhydrides are molecules with…

two acyl groups bonded to the same oxygen atom.

Alternative answer:

two carbonyl groups bonded to the same oxygen atom.

the general formula of acid anyhydrides is ………..

RCOOCOR

(where the R group can be different hydrocarbon chains )

Give the IUPAC name of the molecule with the formula (HCO)2O.

methanoic anhydride

Draw ethanoic anhydride.

Draw a skeletal formula

REMEMBER when naming the acid anhydride you just need to replace the ‘acid’ of the carboxylic acid name with ………..

This is because most of alevel molecules, the carbon chain will be the same length

anhydride

Both carboxylic acid derivatives acid anhydrides and acyl chlorides react with war to form ………………

carboxylic acids

Ethanoic acid smells like…

vinegar

Acyl chlorides…

Select all that apply

A) smell of the acids from which they are derived.

B) react with water.

C) can form an aqueous solution.

Acid anhydrides…

Select all that apply

A) smell of the acids from which they are derived.

B) react with water.

C) can form an aqueous solution.

AB
AB

Acyl chlordes reaction with water is ………….

violent

What is the general formula for acyl chlorides?

…………….
Acyl chlorides contain the ………. functional group.

RCOCl

carbonyl