121-21-1

Basic information

• Product Name: PYRETHRIN 1
• Synonyms: PYRETHRIN 1;(+)-pyrethronyl(+)-trans-chrysanthemate;2,2-dimethyl-3-(2-methyl-1-propenyl)cyclopropanecarboxylicacid2-methyl-4-oxo;2,2-dimethyl-3-(2-methylpropenyl)-cyclopropaneacrylicaciesterwith4-hydr;2,2-dimethyl-3-(2-methylpropenyl)-cyclopropanecarboxylicaciesterwith4-h;2-dimethyl-3-(2-methyl-1-propenyl)-2-methyl-4-cyclopropanecarboxylicaci;2-methyl-4-oxo-3-(2,4-pentadienyl)-2-cyclopenten-2,2-dimethyl-3-(2-methyl-1-pr;2-methyl-4-oxo-3-(penta-2,4-dienyl)cyclopent-2-enylchrysanthemate
• CAS NO: 121-21-1
• Molecular Formula: C₂₁H₂₈O₃
• Molecular Weight: 328.44522
• EINECS: 204-455-8
• Mol File: 121-21-1.mol
• Article Data: 4

Chemical Properties

• Boiling Point: bp0.0005 146-150°
• Flash Point: 182.3°C
• Appearance: /
• Density: 1.5192
• Vapor Pressure: 2.09E-07mmHg at 25°C
• Refractive Index: nD20 1.5242
• Storage Temp.: 0-6°C
• CAS DataBase Reference: PYRETHRIN 1(CAS DataBase Reference)
• NIST Chemistry Reference: PYRETHRIN 1(121-21-1)
• EPA Substance Registry System: PYRETHRIN 1(121-21-1)

Safety Data

• Hazard Codes: Xn,N
• Statements: 20/21/22-50/53
• Safety Statements: 13-60-61
• RIDADR: 2902
• HazardClass: 6.1(b)
• PackingGroup: III
• Hazardous Substances Data: 121-21-1(Hazardous Substances Data)

Usage

General Description

Pyrethrin 1 is a naturally occurring pesticide extracted from the pyrethrum plant, often found in chrysanthemum flower. It is a potent insecticide and is highly sought after for its effectiveness in controlling harmful insects. It targets the insect's nervous system leading to paralysis or death. Despite its destructive capabilities to pests, pyrethrin 1 is considered to be one of the safest pesticides for use around humans and pets due to its low toxicity and biodegradability. However, some care should still be taken as it can cause skin irritation or asthma-like symptoms in some individuals. Additionally, it is toxic to aquatic life and can degrade rapidly in sunlight.

InChI:InChI=1/C21H28O3/c1-7-8-9-10-15-14(4)18(12-17(15)22)24-20(23)19-16(11-13(2)3)21(19,5)6/h7-9,11,16,18-19H,1,10,12H2,2-6H3/b9-8+/t16-,18+,19+/m1/s1

Synthetic route

(1R,3R)-trans-chrysanthemic acid (4638-92-0) + (S)-(+)-pyrethrolone (487-67-2) → pyrethrin I (121-21-1)

Conditions	Yield
Stage #1: (1R,3R)-trans-chrysanthemic acid With 1-methyl-1H-imidazole; p-toluenesulfonyl chloride In acetonitrile at 0 - 5℃; for 0.5h; Inert atmosphere; Stage #2: (S)-(+)-pyrethrolone In acetonitrile at 20 - 25℃; for 2h; Inert atmosphere;	74%

acyl chloride of (1R)-2.2-dimethyl-3t-<2-methyl-propenyl>-cyclopropane-carboxylic acid-(1r) + (S)-5-hydroxy-1-methyl-2-c.4)-yl>-cyclopenten-(1)-one-(3) → pyrethrin I (121-21-1)

Conditions	Yield
With pyridine; benzene

chrysanthemoyl CoA + (S)-(+)-pyrethrolone (487-67-2) → pyrethrin I (121-21-1)

Conditions	Yield
With (maltose-binding protein)-fusedTanacetum cinerariifolium GDSL lipase/esterase,recombinant, molecular weight: 81689 Da In aq. buffer at 25℃; for 0.166667h; pH=7.5; Kinetics; Reagent/catalyst; Enzymatic reaction;

(1R,3R)-trans-chrysanthemic acid (4638-92-0) → pyrethrin I (121-21-1)

Conditions	Yield
Multi-step reaction with 3 steps 1: thionyl chloride / 0.5 h / 50 - 100 °C 2: 1 h / 0 °C / Reflux 3: 1,8-diazabicyclo[5.4.0]undec-7-ene / tetrahydrofuran / 0 °C View Scheme

(1R)-trans-3-(2-methyl-1-propenyl)-2,2-dimethylcyclopropanecarboxylic acid chloride (4489-14-9) + C11H15IO2 → pyrethrin I (121-21-1)

Conditions	Yield
Multi-step reaction with 2 steps 1: 1 h / 0 °C / Reflux 2: 1,8-diazabicyclo[5.4.0]undec-7-ene / tetrahydrofuran / 0 °C View Scheme

C21H29IO3 → pyrethrin I (121-21-1)

Conditions	Yield
With 1,8-diazabicyclo[5.4.0]undec-7-ene In tetrahydrofuran at 0℃;

(S)-4-hydroxy-3-methyl-2-(2-propenyl)-2-cyclopenten-1-one (22373-75-7) → pyrethrin I (121-21-1)

Conditions	Yield
Multi-step reaction with 3 steps 1: [2-(1-methylethoxy-O)phenylmethyl-C](nitrato-O,O'){rel-(2R,5R,7R)-adamantane-2,1-diyl[3-(2,4,6-trimethylphenyl)-1-imidazolidinyl-2-ylidene]}ruthenium / tetrahydrofuran / 12 h / 35 °C 2: 1 h / 0 °C / Reflux 3: 1,8-diazabicyclo[5.4.0]undec-7-ene / tetrahydrofuran / 0 °C View Scheme

(S)-(+)-4-hydroxy-3-methyl-2-(pent-4-en-2-ynyl)-2-cyclopenten-1-one → pyrethrin I (121-21-1)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: hydrogenchloride; zinc / ethanol; water / 16 h / 75 - 80 °C / Inert atmosphere 2.1: 1-methyl-1H-imidazole; p-toluenesulfonyl chloride / acetonitrile / 0.5 h / 0 - 5 °C / Inert atmosphere 2.2: 2 h / 20 - 25 °C / Inert atmosphere View Scheme

ethyl trans-(+/-)-chrysanthemate (97-41-6, 1802-02-4, 7377-84-6, 15543-65-4, 16642-27-6, 34909-55-2, 41641-25-2, 41641-26-3, 41641-27-4) → pyrethrin I (121-21-1)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: potassium hydroxide / ethanol; water / 3 h 2.1: (S)-1-(1-Naphthyl)ethylamine / ethanol / 3 h / 20 °C 3.1: 1-methyl-1H-imidazole; p-toluenesulfonyl chloride / acetonitrile / 0.5 h / 0 - 5 °C / Inert atmosphere 3.2: 2 h / 20 - 25 °C / Inert atmosphere View Scheme

trans-chrysanthemic acid (827-90-7, 2259-14-5, 2935-23-1, 4638-92-0, 10453-89-1, 15259-78-6, 26771-06-2, 26771-11-9, 705-16-8) → pyrethrin I (121-21-1)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: (S)-1-(1-Naphthyl)ethylamine / ethanol / 3 h / 20 °C 2.1: 1-methyl-1H-imidazole; p-toluenesulfonyl chloride / acetonitrile / 0.5 h / 0 - 5 °C / Inert atmosphere 2.2: 2 h / 20 - 25 °C / Inert atmosphere View Scheme

(S)-4-hydroxy-3-methyl-2-(2-propynyl)-cyclopent-2-ene-1-one (77087-34-4) → pyrethrin I (121-21-1)

Conditions

Yield

Multi-step reaction with 3 steps 1.1: copper(l) iodide; tetrakis(triphenylphosphine) palladium(0); triethylamine / toluene / 16 h / 20 - 25 °C / Inert atmosphere 2.1: hydrogenchloride; zinc / ethanol; water / 16 h / 75 - 80 °C / Inert atmosphere 3.1: 1-methyl-1H-imidazole; p-toluenesulfonyl chloride / acetonitrile / 0.5 h / 0 - 5 °C / Inert atmosphere 3.2: 2 h / 20 - 25 °C / Inert atmosphere View Scheme

ethyl 2,2-dimethyl-3-(2-methylpropenyl)cyclopropanecarboxylate (97-41-6) → pyrethrin I (121-21-1)

Conditions	Yield
Multi-step reaction with 4 steps 1.1: sodium hydride / mineral oil / 3 h / Inert atmosphere 2.1: potassium hydroxide / ethanol; water / 3 h 3.1: (S)-1-(1-Naphthyl)ethylamine / ethanol / 3 h / 20 °C 4.1: 1-methyl-1H-imidazole; p-toluenesulfonyl chloride / acetonitrile / 0.5 h / 0 - 5 °C / Inert atmosphere 4.2: 2 h / 20 - 25 °C / Inert atmosphere View Scheme

pyrethrin I (121-21-1) → (1S)-2-methyl-4-oxo-3-pentylcyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate

Conditions	Yield
With palladium 10% on activated carbon; hydrogen In tetrahydrofuran at 20℃; for 4h;	83%

pyrethrin I (121-21-1) → (1S,4R)-4-hydroxy-2-methyl-3-((2Z)-penta-2,4-dien-1-yl)cyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate

Conditions	Yield
With L-Selectride In tetrahydrofuran at 0℃; for 1h; Inert atmosphere; stereoselective reaction;	38%

pyrethrin I (121-21-1) → (S)-2-methyl-4-oxo-3-(penta-1,3-dien-1-yl)cyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate + (1S)-2-methyl-4-oxo-3-((E)-penta-2,4-dien-1-yl)cyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate

Conditions	Yield
With formic acid; palladium 10% on activated carbon In tetrahydrofuran for 5h; Inert atmosphere; Reflux;	A 15% B 9%

pyrethrin I (121-21-1) + acetic acid (64-19-7) → (1S,4S)-4-acetoxy-2-methyl-3-((2Z)-penta-2,4-dien-1-yl)cyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate + (1S,4R)-4-hydroxy-2-methyl-3-((2Z)-penta-2,4-dien-1-yl)cyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate + (1S,4R)-4-acetoxy-2-methyl-3-((2Z)-penta-2,4-dien-1-yl)cyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate

Conditions	Yield
Stage #1: pyrethrin I With 9-bora-bicyclo[3.3.1]nonane In tetrahydrofuran for 5h; Inert atmosphere; Stage #2: acetic acid In tetrahydrofuran for 1h; Inert atmosphere; Reflux;	A n/a B 15% C n/a

pyrethrin I (121-21-1) → (Ξ)-4-ethoxy-3-methyl-2-penta-2c,4-dienyl-cyclopent-2-enone-(2,4-dinitro-phenylhydrazone) (102161-17-1)

Conditions	Yield
With ethanol; sulfuric acid; (2,4-dinitro-phenyl)-hydrazine

pyrethrin I (121-21-1) → (1R,3R)-trans-chrysanthemic acid (4638-92-0)

Conditions	Yield
With potassium hydroxide In ethanol Hydrolysis;

pyrethrin I (121-21-1) → (1R)-2.2-dimethyl-3t-<2-methyl-propenyl>-cyclopropane-carboxylic acid-(1r)-<(S)-4-oxo-2-methyl-3-(pentadien-(1.3c)-yl-(t))-cyclopenten-(2)-yl ester

pyrethrin I (121-21-1) → (1S,4S)-4-acetoxy-2-methyl-3-((2Z)-penta-2,4-dien-1-yl)cyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate

Conditions	Yield
Multi-step reaction with 2 steps 1: sodium tetrahydroborate / tetrahydrofuran; methanol / 3 h / 0 °C 2: triethylamine / dichloromethane / 4.5 h / Inert atmosphere; Reflux View Scheme

pyrethrin I (121-21-1) → (S)-2-methyl-4-oxo-3-((Z)-pent-2-en-1-yl)cyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-en-1-yl)-cyclopropane-1-carboxylate (4466-14-2) + (1S)-2-methyl-4-oxo-3-pentylcyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate

Conditions	Yield
With copper(ll) sulfate pentahydrate; hydrazine hydrate; acetic acid In tetrahydrofuran	A 68 %Chromat. B 25 %Chromat.

pyrethrin I (121-21-1) → (1S,4R)-4-hydroxy-2-methyl-3-((2Z)-penta-2,4-dien-1-yl)cyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate + (1S,4S)-4-hydroxy-2-methyl-3-((2Z)-penta-2,4-dien-1-yl)cyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate

Conditions	Yield
With sodium tetrahydroborate In tetrahydrofuran; methanol at 0℃; for 3h;	A 202 mg B 45 mg

pyrethrin I (121-21-1) → (1S,4R)-4-acetoxy-2-methyl-3-((2Z)-penta-2,4-dien-1-yl)cyclopent-2-en-1-yl (1R,3R)-2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropane-1-carboxylate

Conditions	Yield
Multi-step reaction with 2 steps 1.1: 9-bora-bicyclo[3.3.1]nonane / tetrahydrofuran / 5 h / Inert atmosphere 1.2: 1 h / Inert atmosphere; Reflux 2.1: triethylamine / dichloromethane / 4.5 h / Inert atmosphere; Reflux View Scheme
Multi-step reaction with 2 steps 1: sodium tetrahydroborate / tetrahydrofuran; methanol / 3 h / 0 °C 2: triethylamine / dichloromethane / 4.5 h / Inert atmosphere; Reflux View Scheme

Upstream product

• 100059-03-8 3-hydroxy-undec-10-en-8-yne-2,5-dione 
• 4489-14-9 (1R)-trans-3-(2-methyl-1-propenyl)-2,2-dimethylcyclopropanecarboxylic acid chloride 
• 20549-21-7 (+/-)-4-hydroxy-3-methyl-2-penta-2c,4-dienyl-cyclopent-2-enone 
• 487-67-2 (S)-(+)-pyrethrolone 
• 134053-75-1 4-hydroxy-3-methyl-2-pent-4-en-2-ynyl-cyclopent-2-enone 
• 97-41-6 ethyl 2,2-dimethyl-3-(2-methylpropenyl)cyclopropanecarboxylate 
• 77087-34-4 (S)-4-hydroxy-3-methyl-2-(2-propynyl)-cyclopent-2-ene-1-one 
• 827-90-7 trans-chrysanthemic acid 
• 97-41-6 ethyl trans-(+/-)-chrysanthemate 
• 4638-92-0 (1R,3R)-trans-chrysanthemic acid 
• 22373-75-7 (S)-4-hydroxy-3-methyl-2-(2-propenyl)-2-cyclopenten-1-one 

Downstream Products

• 4638-92-0 (1R,3R)-trans-chrysanthemic acid 
• 102161-17-1 (Ξ)-4-ethoxy-3-methyl-2-penta-2c,4-dienyl-cyclopent-2-enone-(2,4-dinitro-phenylhydrazone) 

Relevant articles and documents

Requirement of catalytic-triad and related amino acids for the acyltransferase activity of Tanacetum Cinerariifolium gdsl lipase/esterase tcglip for ester-bond formation in pyrethrin biosynthesis

We have recently discovered that a GDSL lipase/ esterase (TcGLIP) in Tanacetum cinerariifolium catalyzed acyltransferase activity to form an ester bond in the natural insecticide, pyrethrin. TcGLIP contained Ser40 in Block I, Gly64 in Block II, Asn168 in Block III and Asp318 and His321 in Block V, suggesting underlying hydrolase activity, although little is known about their role in acyltransferase activity. We expressed TcGLIP here in Esherichia coli as a fusion with maltosebinding protein (MBP), part of the fusion being cleaved with a protease to obtain MBP-free TcGLIP. A kinetic analysis revealed that the MBP moiety scarcely influenced the kinetic parameters. The effects on acyltransferase activity of mutations of Gly64, Asn168, Asp318 and His321 were investigated by using MBP-fused TcGLIP. Mutations of these amino acids markedly reduced the acyltransferase activity, suggesting their critical role in the production of pyrethrins.

Synthesis of pyrethroids and pyrethroid-containing compositions

The present invention provides methods for synthesizing pyrethroid compounds. The methods include forming a first reaction comprising an olefin and an allethrolone-type unsaturated alcohol under conditions sufficient to form a metathesis product and converting the metathesis product to the pyrethroid. Methods of the invention can be used to prepare compounds including pyrethrin I, cinerin I, jasmolin I, pyrethrin II, cinerin II, and jasmolin II as well as other synthetic pyrethroid compounds. Insecticidal compositions and methods for controlling insects are also described.