120983-72-4

Basic information

• Product Name: Ethanone, 2-chloro-1-(1-chlorocyclopropyl)- (9CI)
• Synonyms: Ethanone, 2-chloro-1-(1-chlorocyclopropyl)- (9CI);Ethanone, 2-chloro-1-(1-chlorocyclopropyl)-;2-CHLORO-1-(1-CHLOROCYCLOPROPYL)ETHAN-1-ONE
• CAS NO: 120983-72-4
• Molecular Formula: C₅H₆Cl₂O
• Molecular Weight: 153.00654
• Product Categories: ACETYLHALIDE
• Mol File: 120983-72-4.mol
• Article Data: 14

Chemical Properties

• Boiling Point: 201.961 °C at 760 mmHg
• Flash Point: 79.235 °C
• Appearance: /
• Density: 1.351 g/cm³
• Vapor Pressure: 0.3mmHg at 25°C
• Refractive Index: 1.493
• Storage Temp.: under inert gas (nitrogen or Argon) at 2-8°C
• Water Solubility: 5.91g/L at 20℃
• CAS DataBase Reference: Ethanone, 2-chloro-1-(1-chlorocyclopropyl)- (9CI)(CAS DataBase Reference)
• NIST Chemistry Reference: Ethanone, 2-chloro-1-(1-chlorocyclopropyl)- (9CI)(120983-72-4)
• EPA Substance Registry System: Ethanone, 2-chloro-1-(1-chlorocyclopropyl)- (9CI)(120983-72-4)

Safety Data

• Hazardous Substances Data: 120983-72-4(Hazardous Substances Data)

Usage

Uses

2-chloro-1-(1-chlorocyclopropyl)ethan-1-one is a chemical intermediate, mainly used for the synthesis of prothioconazole.

Flammability and Explosibility

Notclassified

Synthesis

2-chloro-1-(1-chlorocyclopropyl)ethan-1-one was prepared by 1-(1-chlorocyclopropyl)ethanone stirred in DCM and methanol with chlorine gas at 0℃ for 3h.

InChI:InChI=1/C5H6Cl2O/c6-3-4(8)5(7)1-2-5/h1-3H2

Synthetic route

1-chlorocyclopropyl methyl ketone (63141-09-3) → 1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4)

Conditions	Yield
With chlorine at 10 - 25℃; under 760.051 Torr; for 2h; Temperature; Reagent/catalyst;	98.5%
With sodium nitrate; trichloroisocyanuric acid; antimonypentachloride at 60℃; for 4h; Reagent/catalyst; Solvent; Temperature;	96.8%
With iron(III) chloride; tetrabutylammomium bromide; chlorine In dichloromethane at 15 - 25℃; for 5h; Reagent/catalyst; Temperature;	93.1%

Cyclopropyl methyl ketone (765-43-5) → 1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4)

Conditions	Yield
With N-chloro-succinimide In dichloromethane at 0 - 20℃;	92%
With phosgene In methanol; chloroform at 5 - 15℃; for 3h; Temperature; Reagent/catalyst; Solvent; Reflux;	71.95%

5-chloro-2-pentanone (5891-21-4) → 1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4)

Conditions	Yield
Stage #1: 5-chloro-2-pentanone With thionyl chloride In dichloromethane at 0 - 40℃; for 4h; Stage #2: With tetrabutylammomium bromide; sodium hydroxide In dichloromethane at 40℃; for 3h; Solvent; Temperature; Reagent/catalyst;	60%

3, 5-dichloro-2-pentanone (58371-98-5) → 1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4)

Conditions	Yield
With tetrabutylammomium bromide; sodium hydroxide In water at 20 - 90℃; for 0.583333h; Reagent/catalyst; Heating;

1,3,5-trichloro-2-pentanone → 1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4)

Conditions	Yield
With sodium hydroxide In dichloromethane; water at 0℃; for 0.166667h; Reagent/catalyst; Flow reactor;

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) + 1-chloro-2-(chloromethyl)benzene (611-19-8) → 3-chloro-2-(1-chloro-cycloprop-1-yl)-1-(2-chloro-phenyl)-propan-2-ol

Conditions	Yield
Stage #1: 1-chloro-2-(chloromethyl)benzene With iodine; magnesium In 2-methyltetrahydrofuran; tert-butyl methyl ether at 50℃; for 0.5h; Stage #2: 1-chlorocyclopropyl-2-chloro-ethan-1-one In tert-butyl methyl ether at 0℃; for 0.00833333h;	95.3%
Stage #1: 1-chloro-2-(chloromethyl)benzene With iodine; magnesium In 2-methyltetrahydrofuran; tert-butyl methyl ether at 25 - 50℃; for 4.5h; Inert atmosphere; Large scale; Stage #2: 1-chlorocyclopropyl-2-chloro-ethan-1-one In 2-methyltetrahydrofuran; tert-butyl methyl ether at 0 - 5℃; for 1h; Solvent; Large scale;	94%
Stage #1: 1-chloro-2-(chloromethyl)benzene With iodine; magnesium In tetrahydrofuran for 1h; Cooling with ice; Stage #2: 1-chlorocyclopropyl-2-chloro-ethan-1-one In tetrahydrofuran for 1h; Cooling with ice;	89%
Stage #1: 1-chloro-2-(chloromethyl)benzene With iodine; magnesium In 1,2-dimethoxyethane Grignard Reaction; Stage #2: 1-chlorocyclopropyl-2-chloro-ethan-1-one In 1,2-dimethoxyethane; toluene at 20 - 25℃; for 2h; Solvent; Grignard Reaction;	81%

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) + allylmagnesium bromide (1730-25-2) → 1-chloro-2-(1-chlorocyclopropyl)-4-pentene-2-ol (1311370-58-7)

Conditions	Yield
With ammonium chloride In diethyl ether at -50℃; for 1.33333h; Inert atmosphere;	77%
Stage #1: 1-chlorocyclopropyl-2-chloro-ethan-1-one; allylmagnesium bromide In diethyl ether at -50℃; for 2.33333h; Inert atmosphere; Cooling with ice; Stage #2: With ammonium chloride In diethyl ether; water Cooling with ice;

3-chloro-4-methylpyridine (72093-04-0) + 1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 3-chloro-4-{[2-(1-chlorocyclopropyl)oxiran-2-yl]methyl}pyridine

Conditions	Yield
Stage #1: 3-chloro-4-methylpyridine With lithium diisopropyl amide In tetrahydrofuran at -70 - -30℃; for 0.0833333h; Inert atmosphere; Stage #2: 1-chlorocyclopropyl-2-chloro-ethan-1-one In tetrahydrofuran at -70 - 20℃; for 1h; Inert atmosphere;	73%
Stage #1: 3-chloro-4-methylpyridine With lithium diisopropyl amide In tetrahydrofuran at -70℃; for 0.0833333h; Inert atmosphere; Stage #2: 1-chlorocyclopropyl-2-chloro-ethan-1-one In tetrahydrofuran at -70 - -30℃; for 1h; Inert atmosphere;	73%

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) + vinyl magnesium bromide (1826-67-1) → 1-chloro-2-(1-chlorocyclopropyl)-3-buten-2-ol

Conditions	Yield
Stage #1: 1-chlorocyclopropyl-2-chloro-ethan-1-one; vinyl magnesium bromide In tetrahydrofuran at -20 - 0℃; Inert atmosphere; Stage #2: With ammonium chloride In tetrahydrofuran; water Cooling with ice;	67%

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) + 1-allyl-1H-imidazole-4-carbonitrile → 1-allyl-3-[2-(1-chlorocyclopropyl)-2-oxoethyl]-4-cyano-1H-imidazol-3-ium iodide

Conditions	Yield
With potassium iodide In methanol at 70℃; for 46h;	46%
With potassium iodide In methanol at 70℃; for 46h;

1H-tetrazole (288-94-8) + 1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 1-(1-chlorocyclopropyl)-2-(tetrazol-2-yl)ethanone + 1-(1-chlorocyclopropyl)-2-(tetrazol-1-yl)ethanone

Conditions	Yield
Stage #1: 1H-tetrazole With 1,8-diazabicyclo[5.4.0]undec-7-ene In acetonitrile at 21℃; for 0.0833333h; Inert atmosphere; Stage #2: 1-chlorocyclopropyl-2-chloro-ethan-1-one In acetonitrile at 21 - 40℃; for 2h;	A 10.4% B 34.7%

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) + tert-butyl 4-(3-carbamothioyl-5-oxo-4,5-dihydropyrazolo[1,5-a]pyrimidin-7-yl)piperidine-1-carboxylate → tert-butyl 4-{3-[4-(1-chlorocyclopropyl)-1,3-thiazol-2-yl]-5-oxo-4,5-dihydropyrazolo[1,5-a]pyrimidin-7-yl}piperidine-1-carboxylate

Conditions	Yield
With tetra-(n-butyl)ammonium iodide; N-ethyl-N,N-diisopropylamine In ethanol at 70℃; for 1h;	30%

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) + 1-bromovinylbenzene (98-81-7) + ammonium chloride → 1-chloro-2-(1-chlorocyclopropyl)-3-phenyl-but-3-en-2-ol

Conditions	Yield
With magnesium In diethyl ether

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) + 4-chloro-phenol (106-48-9) → 1-chlorocyclopropyl-2-(4-chlorophenoxy)-ethan-1-one

Conditions	Yield
With potassium carbonate In water; toluene

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) + 4-chloro-phenol (106-48-9) → 1-chlorocyclopropyl-4-chlorophenoxymethyl ketone

Conditions	Yield
With potassium carbonate In ethyl acetate; acetonitrile

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) + 4-Fluorobenzyl bromide (459-46-1) → 1-chloro-2-(1-chlorocyclopropyl)-3-(4-fluorophenyl)-propan-2-ol

Conditions	Yield
With magnesium; acetic acid In diethyl ether; water

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 2-(1-chlorocyclopropyl)-2-(2,2-dichlorocyclopropyl)oxirane

Conditions	Yield
Multi-step reaction with 2 steps 1.1: tetrahydrofuran / -20 - 0 °C / Inert atmosphere 1.2: Cooling with ice 2.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / water / 32 h / 60 - 80 °C View Scheme

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 1-(1-chlorocyclopropyl)-1-(2,2-dichlorocyclopropyl)-2-(1H-1,2,4-triazol-1-yl)ethanol

Conditions	Yield
Multi-step reaction with 3 steps 1.1: tetrahydrofuran / -20 - 0 °C / Inert atmosphere 1.2: Cooling with ice 2.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / water / 32 h / 60 - 80 °C 3.1: potassium carbonate; potassium tert-butylate / 1-methyl-pyrrolidin-2-one / 5 h / 80 °C / Inert atmosphere View Scheme

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 2-(1-chlorocyclopropyl)-2-(2,2-dibromocyclopropylmethyl)oxirane

Conditions	Yield
Multi-step reaction with 2 steps 1.1: diethyl ether / 2.33 h / -50 °C / Inert atmosphere; Cooling with ice 1.2: Cooling with ice 2.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / water / 7 h / 20 - 80 °C View Scheme
Multi-step reaction with 2 steps 1: zinc; ammonium chloride / water; tetrahydrofuran / 3.17 h / 35 °C 2: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / water / 7 h / 20 - 80 °C View Scheme
Multi-step reaction with 3 steps 1.1: diethyl ether / 2.33 h / -50 °C / Inert atmosphere; Cooling with ice 1.2: Cooling with ice 2.1: sodium hydroxide; water / tetrahydrofuran / 4 h / 20 °C 3.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / dichloromethane; water / 15 h / 60 °C View Scheme
Multi-step reaction with 3 steps 1: zinc; ammonium chloride / water; tetrahydrofuran / 3.17 h / 35 °C 2: sodium hydroxide; water / tetrahydrofuran / 4 h / 20 °C 3: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / dichloromethane; water / 15 h / 60 °C View Scheme
Multi-step reaction with 2 steps 1: ammonium chloride / diethyl ether / 1.33 h / -50 °C / Inert atmosphere 2: N-benzyl-N,N,N-triethylammonium chloride; sodium hydroxide / water / 7 h / 20 - 80 °C View Scheme

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 2-(1-chlorocyclopropyl)-1-(2,2-dibromocyclopropyl)-3-(1H-1,2,4-triazole-1-yl)propane-2-ol

Conditions	Yield
Multi-step reaction with 3 steps 1.1: diethyl ether / 2.33 h / -50 °C / Inert atmosphere; Cooling with ice 1.2: Cooling with ice 2.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / water / 7 h / 20 - 80 °C 3.1: potassium carbonate; sodium t-butanolate / N,N-dimethyl-formamide / 2 h / 90 °C View Scheme
Multi-step reaction with 3 steps 1: zinc; ammonium chloride / water; tetrahydrofuran / 3.17 h / 35 °C 2: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / water / 7 h / 20 - 80 °C 3: potassium carbonate; sodium t-butanolate / N,N-dimethyl-formamide / 2 h / 90 °C View Scheme
Multi-step reaction with 4 steps 1.1: diethyl ether / 2.33 h / -50 °C / Inert atmosphere; Cooling with ice 1.2: Cooling with ice 2.1: sodium hydroxide; water / tetrahydrofuran / 4 h / 20 °C 3.1: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / dichloromethane; water / 15 h / 60 °C 4.1: potassium carbonate; sodium t-butanolate / N,N-dimethyl-formamide / 2 h / 90 °C View Scheme
Multi-step reaction with 4 steps 1: zinc; ammonium chloride / water; tetrahydrofuran / 3.17 h / 35 °C 2: sodium hydroxide; water / tetrahydrofuran / 4 h / 20 °C 3: sodium hydroxide; N-benzyl-N,N,N-triethylammonium chloride / dichloromethane; water / 15 h / 60 °C 4: potassium carbonate; sodium t-butanolate / N,N-dimethyl-formamide / 2 h / 90 °C View Scheme

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 2-(1-chlorocyclopropyl)-2-(2-propenyl)oxirane (1311370-67-8)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: diethyl ether / 2.33 h / -50 °C / Inert atmosphere; Cooling with ice 1.2: Cooling with ice 2.1: sodium hydroxide; water / tetrahydrofuran / 4 h / 20 °C View Scheme
Multi-step reaction with 2 steps 1: zinc; ammonium chloride / water; tetrahydrofuran / 3.17 h / 35 °C 2: sodium hydroxide; water / tetrahydrofuran / 4 h / 20 °C View Scheme

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) + allyl bromide (106-95-6) → 1-chloro-2-(1-chlorocyclopropyl)-4-pentene-2-ol (1311370-58-7)

Conditions	Yield
With ammonium chloride; zinc In tetrahydrofuran; water at 35℃; for 3.16667h;

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → C13H14Cl2N4OS

Conditions	Yield
Multi-step reaction with 3 steps 1.1: lithium diisopropyl amide / tetrahydrofuran / 0.08 h / -70 - -30 °C / Inert atmosphere 1.2: 1 h / -70 - 20 °C / Inert atmosphere 2.1: potassium tert-butylate; potassium carbonate / N,N-dimethyl-formamide / 5 h / 40 °C 3.1: lithium diisopropyl amide / tetrahydrofuran / 1 h / -78 - 10 °C 3.2: -10 - 20 °C View Scheme

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 2-(1-chlorocyclopropyl)-1-(3-chloropyridin-4-yl)-3-(1H-1,2,4-triazol-1-yl)propan-2-ol

Conditions	Yield
Multi-step reaction with 2 steps 1.1: lithium diisopropyl amide / tetrahydrofuran / 0.08 h / -70 - -30 °C / Inert atmosphere 1.2: 1 h / -70 - 20 °C / Inert atmosphere 2.1: potassium tert-butylate; potassium carbonate / N,N-dimethyl-formamide / 5 h / 40 °C View Scheme

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → di-{1-[2-(1-chlorocyclopropyl)-3-(2-chloro-phenyl)-2-hydroxy-propyl-1]-1,2,4-triazol-5-yl} disulphide (199391-98-5)

Conditions	Yield
Multi-step reaction with 2 steps 1.1: iodine; magnesium / tetrahydrofuran / 1 h / Cooling with ice 1.2: 1 h / Cooling with ice 2.1: potassium carbonate / N,N-dimethyl-formamide / 2 h / 50 °C View Scheme

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → prothioconazole (303048-98-8, 303048-99-9, 856220-33-2)

Conditions	Yield
Multi-step reaction with 3 steps 1.1: iodine; magnesium / tetrahydrofuran / 1 h / Cooling with ice 1.2: 1 h / Cooling with ice 2.1: potassium carbonate / N,N-dimethyl-formamide / 2 h / 50 °C 3.1: zinc / methanol / 3 h / 30 °C View Scheme

1-allyl-4-chloro-1H-imidazole + 1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 1-allyl-4-chloro-3-[2-(1-chlorocyclopropyl)-2-oxoethyl]-1H-imidazol-3-ium iodide

Conditions	Yield
With potassium iodide In methanol at 20 - 70℃; for 22h;	34.6 g

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 2-(1-chlorocyclopropyl)-3-(2-fluorophenyl)-1-(tetrazol-1-yl)butan-2-ol + 2-(1-chlorocyclopropyl)-3-(2-fluorophenyl)-1-(tetrazol-1-yl)butan-2-ol

Conditions	Yield
Multi-step reaction with 3 steps 1.1: 1,8-diazabicyclo[5.4.0]undec-7-ene / acetonitrile / 0.08 h / 21 °C / Inert atmosphere 1.2: 2 h / 21 - 40 °C 2.1: ethylene dibromide; magnesium / diethyl ether / 0.67 h / 0 - 5 °C / Inert atmosphere 2.2: 0.83 h / 0 - 5 °C 3.1: hydrogen; palladium on activated charcoal / methanol / 21 °C View Scheme

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 2-(1-chlorocyclopropyl)-1-phenyl-3-(tetrazol-1-yl)propan-2-ol

Conditions	Yield
Multi-step reaction with 2 steps 1.1: 1,8-diazabicyclo[5.4.0]undec-7-ene / acetonitrile / 0.08 h / 21 °C / Inert atmosphere 1.2: 2 h / 21 - 40 °C 2.1: manganese chloride bis(lithium chloride) / tetrahydrofuran / 0.33 h / 0 °C / Inert atmosphere 2.2: 2 h / 0 °C View Scheme

1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) → 2-(1-chlorocyclopropyl)-3-(2-fluorophenyl)-1-(tetrazol-1-yl)but-3-en-2-ol

Conditions	Yield
Multi-step reaction with 2 steps 1.1: 1,8-diazabicyclo[5.4.0]undec-7-ene / acetonitrile / 0.08 h / 21 °C / Inert atmosphere 1.2: 2 h / 21 - 40 °C 2.1: ethylene dibromide; magnesium / diethyl ether / 0.67 h / 0 - 5 °C / Inert atmosphere 2.2: 0.83 h / 0 - 5 °C View Scheme

formaldehyd (50-00-0) + 1-chlorocyclopropyl-2-chloro-ethan-1-one (120983-72-4) + ammonium thiocyanate (1147550-11-5) + 1-chloro-2-(chloromethyl)benzene (611-19-8) → prothioconazole (303048-98-8, 303048-99-9, 856220-33-2)

Conditions	Yield
Stage #1: 1-chloro-2-(chloromethyl)benzene With iodine; magnesium at 30℃; for 3h; Inert atmosphere; Stage #2: 1-chlorocyclopropyl-2-chloro-ethan-1-one for 2h; Inert atmosphere; Stage #3: formaldehyd; ammonium thiocyanate Further stages;

Upstream product

• 517-23-7 3-acetyl-2-oxo-4,5-dihydrofuran 
• 5891-21-4 5-chloro-2-pentanone 
• 765-43-5 Cyclopropyl methyl ketone 
• 58371-98-5 3, 5-dichloro-2-pentanone 
• 63141-09-3 1-chlorocyclopropyl methyl ketone 

Downstream Products

• 199391-98-5 di-{1-[2-(1-chlorocyclopropyl)-3-(2-chloro-phenyl)-2-hydroxy-propyl-1]-1,2,4-triazol-5-yl} disulphide 
• 303048-98-8 prothioconazole 
• 222408-90-4 [2-(1-chlorocyclopropyl-1-yl)-1-(2-chlorophenyl)-2-hydroxy-3-propane]-(1,2,4-triazolidine-3-thiol-1-yl) 

Relevant articles and documents

AN INDUSTRIAL SCALE PROCESS FOR THE PREPARATION OF PROTHIOCONAZOLE

The present invention relates to an industrial scale process for the preparation of Prothioconazole (I), which is simple, economical, efficient, user and environment friendly, moreover commercially viable with higher yield and greater chemical purity.

Preparation method 2 - chloro -1 - (1 - chlorocyclopropyl) ethanone

The invention discloses a preparation method of 2-chloro-1-(1-chlorocyclopropyl)ethanone. The method comprises the steps as follows: in the presence of a Lewis acid salt catalyst and a quaternary ammonium salt phase transfer catalyst, chlorine is introduced into a solvent system with 1-acetyl-1-chlorocyclopropane dissolved or directly introduced into 1-acetyl-1-chlorocyclopropane, the reaction temperature is controlled at 5-25 DEG C for chlorination, and 2-chloro-1-(1-chlorocyclopropyl)ethanone is prepared. 2-chloro-1-(1-chlorocyclopropyl)ethanone prepared with the method has the advantage that content and molar yield can reach 90% or higher.

Method for preparing 1-chloro-1-(chloroacetyl) cyclopropane

The invention provides a method for preparing 1-chloro-1 (chloroacetyl) cyclopropane by using a microchannel reactor. The method comprises the steps of B) reacting 1, 3, 5-trichloro-2-pentanone with an alkali liquor in a solvent at a temperature of -5 to 10 DEG C and a pressure of 1.0 to 10.0 bar in the microchannel reactor for 5 to 30 minutes to obtain 1-chloro-1 (chloroacetyl) cyclopropane. Themethod disclosed by the invention is good in selectivity, high in conversion rate and high in product purity, and eliminates polysubstitution byproducts from a reaction source; the method is free of high-temperature and high-pressure reaction and convenient to operate; and moreover, the amplification effect of the reaction is small, and industrial production is facilitated.