121-20-0

Basic information

• Product Name: 3-(but-2-enyl)-2-methyl-4-oxocyclopent-2-enyl2,2-dimethyl-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)cyclopropanecarboxylate
• Synonyms: 3-(but-2-enyl)-2-methyl-4-oxocyclopent-2-enyl2,2-dimethyl-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)cyclopropanecarboxylate;Cyclopropanecarboxylic acid, 3-(1E)-3-methoxy-2-methyl-3-oxo-1-propenyl-2,2-dimethyl-, (1S)-3-(2Z)-2-butenyl-2-methyl-4-oxo-2-cyclopenten-1-yl ester, (1R,3R)-;cinerin II 3-(but-2-enyl)-2-methyl-4-oxocyclopent-2-enyl 2,2-dimethyl-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)cyclopropanecarboxylate;(1R,3R)-3-[(E)-3-Methoxy-2-methyl-3-oxo-1-propenyl]-2,2-dimethylcyclopropanecarboxylic acid (S)-3-[(Z)-2-butenyl]-2-methyl-4-oxo-2-cyclopenten-1-yl;(1R,3R)-3-[(1E)-3-Methoxy-2-Methyl-3-oxo-1-propen-1-yl]-2,2-diMethylcyclopropanecarboxylic Acid (1S)-3-(2Z)-2-Buten-1-yl-2-Methyl-4-oxo-2-cyclopenten-1-yl Ester;Cinerin Ⅱ
• CAS NO: 121-20-0
• Molecular Formula: C₂₁H₂₈O₅
• Molecular Weight: 359.43608
• EINECS: 204-454-2
• Product Categories: Chiral Reagents
• Mol File: 121-20-0.mol
• Article Data: 1

Chemical Properties

• Boiling Point: bp0.001 182-184°
• Flash Point: 195.3°C
• Appearance: /
• Density: 1.12g/cm³
• Vapor Pressure: 2.01E-08mmHg at 25°C
• Refractive Index: nD20 1.5183
• CAS DataBase Reference: 3-(but-2-enyl)-2-methyl-4-oxocyclopent-2-enyl2,2-dimethyl-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)cyclopropanecarboxylate(CAS DataBase Reference)
• NIST Chemistry Reference: 3-(but-2-enyl)-2-methyl-4-oxocyclopent-2-enyl2,2-dimethyl-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)cyclopropanecarboxylate(121-20-0)
• EPA Substance Registry System: 3-(but-2-enyl)-2-methyl-4-oxocyclopent-2-enyl2,2-dimethyl-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)cyclopropanecarboxylate(121-20-0)

Safety Data

• Hazard Codes: Xn,N
• Statements: 22-50/53
• Safety Statements: 60-61
• RIDADR: 2902
• HazardClass: 6.1(b)
• PackingGroup: III
• Hazardous Substances Data: 121-20-0(Hazardous Substances Data)

Usage

Description

3-(but-2-enyl)-2-methyl-4-oxocyclopent-2-enyl2,2-dimethyl-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)cyclopropanecarboxylate is a complex organic compound with a unique structure that features a cyclopentane ring, multiple methyl and oxo groups, and a cyclopropanecarboxylate moiety. It is an active insecticidal constituent found in pyrethrum flowers.

Uses

Used in Pest Control Industry:
3-(but-2-enyl)-2-methyl-4-oxocyclopent-2-enyl2,2-dimethyl-3-(3-methoxy-2-methyl-3-oxoprop-1-enyl)cyclopropanecarboxylate is used as an insecticide for controlling a variety of pests. It is effective due to its ability to target the nervous system of insects, causing paralysis and death. However, it is important to note that this compound oxidizes rapidly and becomes inactive in the presence of air, which may limit its effectiveness over time.

InChI:InChI=1/C21H28O5/c1-7-8-9-14-13(3)17(11-16(14)22)26-20(24)18-15(21(18,4)5)10-12(2)19(23)25-6/h7-8,10,15,17-18H,9,11H2,1-6H3/b8-7+,12-10+/t15-,17-,18+/m1/s1

Upstream product

• 97-41-6 ethyl 2,2-dimethyl-3-(2-methylpropenyl)cyclopropanecarboxylate 
• 74-88-4 methyl iodide 
• 3894-82-4 (S,Z)-2-(but-2-en-1-yl)-4-hydroxy-3-methylcyclopent-2-en-1-one 
• 93132-69-5 (1R,3R)-2,2-Dimethyl-3-((E)-2-methyl-3-oxoprop-1-en-1-yl)cyclopropane-1-carboxylic Acid 
• 35867-05-1 methyl (1R)-trans-2,2-dimethyl-3-[(E)-2-methyl-3-oxo-1-propenyl]cyclopropanecarboxylate 
• 77087-34-4 (S)-4-hydroxy-3-methyl-2-(2-propynyl)-cyclopent-2-ene-1-one 
• 4638-92-0 (1R,3R)-trans-chrysanthemic acid 
• 827-90-7 trans-chrysanthemic acid 
• 97-41-6 ethyl trans-(+/-)-chrysanthemate 
• 27335-33-7 methyl (1R,3R)-3-formyl-2,2-dimethylcyclopropanecarboxylate 

Relevant articles and documents

Total Syntheses of All Six Chiral Natural Pyrethrins: Accurate Determination of the Physical Properties, Their Insecticidal Activities, and Evaluation of Synthetic Methods

Chiral total syntheses of all six insecticidal natural pyrethrins (three pyrethrin I and three pyrethrin II compounds) contained in the chrysanthemum (pyrethrum) flower were performed. Three common alcohol components [(S)-cinerolone, (S)-jasmololone, and (S)-pyrethrolone] were synthesized: (i) straightforward Sonogashira-type cross-couplings using available (S)-4-hydroxy-3-methyl-2-(2-propynyl)cyclopent-2-en-1-ones (the prallethrin alcohol) for (S)-cinerolone (overall 52% yield, 98% ee) and (S)-pyrethrolone (overall 54% yield, 98% ee) and (ii) traditional decarboxylative-aldol condensation and lipase-catalyzed optical resolution for (S)-jasmololone (overall 16% yield, 96% ee). Two counter acid segments [(1R,3R)-chrysanthemic acid (A) and (1R,3R)-second chrysanthemic acid precursor (B)] were prepared: (i) C(1) epimerization of ethyl (±)-chrysanthemates and optical resolution using (S)-naphthylethylamine to afford A (96% ee) and (ii) concise derivatization of A to B (96% ee). All six pyrethrin esters (cinerin I/II, jasmolin I/II, and pyrethrin I/II) were successfully synthesized utilizing an accessible esterification reagent (TsCl/N-methylimidazole). To investigate the stereostructure-activity relationship, all four chiral stereoisomers of cinerin I were synthesized. Three alternative syntheses of (±)-jasmololone were investigated (methods utilizing Piancatelli rearrangement, furan transformation, and 1-nitropropene transformation). Insecticidal activity assay (KD50 and IC50) against the common mosquito (Culex pipiens pallens) revealed that (i) pyrethrin I > pyrethrin II, (ii) pyrethrin I (II) > cinerin I (II) ? jasmolin I (II), and (iii) "natural" cinerin I ? three "unnatural" cinerin I compounds (apparent chiral discrimination).