Question

Kepone, aldrin, and chlordane are synthesized from hexachlorocyclopentadiene and other five-membered ring compounds. Show how these three pesticides are composed of two five-membered rings.

Short answer

Kepone^® or chlordecone is an organochlorine compound and is colourless. It is an insecticide and is persistent organic pollutant that was banned globally in 2009. It is soluble in acetone, ketone and slightly soluble in benzene. It is synthesized from hexachlorocyclopentadiene and upon retrosynthetic analysis, it was determined that structure of kepone is made up of two five-membered rings. Bond-cleavage resulted in formation of two separate five-membered rings as shown in the diagram by dotted lines.

Step-by-step solution

Step-1. Explanation of part (a):

Kepone^® or chlordecone is an organochlorine compound and is colourless. It is an insecticide and is persistent organic pollutant that was banned globally in 2009. It is soluble in acetone, ketone and slightly soluble in benzene. It is synthesized from hexachlorocyclopentadiene and upon retrosynthetic analysis, it was determined that structure of kepone is made up of two five-membered rings. Bond-cleavage resulted in formation of two separate five-membered rings as shown in the diagram by dotted lines.

Step-2. Explanation of part (b):

Aldrin^® is an organochlorine insecticide and is highly toxic to ecosystem and that’s why banned in most countries in 1990. It is a persistent organic pollutant. It dissolves very well in organic solvents, such as ketones and paraffins. It is synthesized from hexachlorocyclopentadiene and upon retrosynthetic analysis, it was determined that structure of Aldrin is made up of two five-membered rings. Bond-cleavage resulted in formation of two separate five-membered rings as shown in the diagram by dotted lines.

Step-3. Explanation of part (c):

Chlordane^® is an organochlorine compound that was used as a pesticide. It is classified as an organic pollutant hazardous to human health. It is resistant to degradation in the environment and exposure to this compound has been linked to cancers, ulcers etc. It is synthesized from hexachlorocyclopentadiene and upon retrosynthetic analysis, it was determined that structure of Chlordane is made up of two five-membered rings. Bond-cleavage resulted in formation of two separate five-membered rings as shown in the diagram by dotted lines.