90428-87-8

Upstream product

• 77832-42-9 (R)-4-hydroxy-3-methyl-2-(2-propynyl)-2-cyclopenten-1-one 
• 124-63-0 methanesulfonyl chloride 

Downstream Products

• 77832-42-9 (R)-4-hydroxy-3-methyl-2-(2-propynyl)-2-cyclopenten-1-one 
• 77087-34-4 (S)-4-hydroxy-3-methyl-2-(2-propynyl)-cyclopent-2-ene-1-one 
• 95413-30-2 (R)-2-methyl-4-oxo-3-(2-propynyl)-2-cyclopentenyl methanesulfonate 

Relevant academic research and scientific papers

Preparation of (4S)-4-hydroxy-3-methyl-2-(2′-propynyl)-2-cyclopentenone by combination of enzymatic hydrolysis and chemical transformation

(4S)-4-Hydroxy-3-methyl-2-(2′-propynyl)-2-cyclopentenone ((S)-2), which is an important alcohol moiety of optically active pyrethroid insecticides, was prepared from the corresponding racemic acetate ((±)-1) by the combination of enzymatic hydrolysis and chemical transformation in high chemical and optical yields.

Process for producing optically active cyclopentenolones

Optically active cyclopentenolones, which are useful as an intermediate of pyrethroid insecticides, are produced from racemic cyclopentenolones according to the following procedures; (1) asymmetric hydrolysis of racemic carboxylate esters of the cyclopentenolones, (2) nitrate- or sulfonate-esterification of the asymmetrical hydrolysis products, and (3) hydrolysis of the esterification products.